| Prefix | Namespace | Title |
| acco | http://www.ebsemantics.net/acco# | Accomodation Ontology |
| acl | http://www.w3.org/ns/auth/acl# | Basic Access Control ontology |
| ad | http://schemas.talis.com/2005/address/schema# | Address Schema |
| af | http://purl.org/ontology/af/ | Audio Features Ontology |
| agls | http://www.agls.gov.au/agls/terms/ | AGLS Metadata Terms |
| aiiso | http://purl.org/vocab/aiiso/schema# | Academic Institution Internal Structure Ontology |
| akt | http://www.aktors.org/ontology/portal# | AKT Reference Ontology |
| akts | http://www.aktors.org/ontology/support# | AKT Support Ontology |
| ao | http://purl.org/ontology/ao/core# | Association Ontology |
| api | http://purl.org/linked-data/api/vocab# | Linked Data API Vocabulary |
| arch | http://purl.org/archival/vocab/arch# | Archival collections ontology |
| being | http://purl.org/ontomedia/ext/common/being# | OntoMedia Being Representation |
| bibo | http://purl.org/ontology/bibo/ | The Bibliographic Ontology |
| bibtex | http://purl.org/net/nknouf/ns/bibtex# | BibTeX ontology |
| bio | http://purl.org/vocab/bio/0.1/ | BIO: A vocabulary for biographical information |
| biol | http://purl.org/NET/biol/ns# | Biological Taxonomy Vocabulary 0.2 (Core) |
| biopax | http://www.biopax.org/release/biopax-level3.owl# | BioPAX Level 3 ontology |
| biotop | http://purl.org/biotop/biotop.owl# | BioTop |
| biro | http://purl.org/spar/biro/ | The Bibliographic Reference Ontology |
| c4n | http://vocab.deri.ie/c4n# | Call for Anything vocabulary |
| c4o | http://purl.org/spar/c4o/ | C4O, the Citation Counting and Context Characterization Ontology |
| cal | http://www.w3.org/2002/12/cal/ical# | Internet Calendaring and Scheduling Core Object Specification |
| cc | http://creativecommons.org/ns# | Creative Commons Rights Expression Language |
| cco | http://purl.org/ontology/cco/core# | Cognitive Characteristics Ontology |
| ceo | http://www.ebusiness-unibw.org/ontologies/consumerelectronics/v1# | Consumer Electronics Ontology |
| cert | http://www.w3.org/ns/auth/cert# | The Cert Ontology |
| cgov | http://reference.data.gov.uk/def/central-government/ | Central Government Ontology |
| chord | http://purl.org/ontology/chord/ | The OMRAS2 Chord Ontology |
| cito | http://purl.org/spar/cito/ | CiTO, the Citation Typing Ontology |
| cmo | http://purl.org/twc/ontologies/cmo.owl# | Conceptual Model Ontology |
| cnt | http://www.w3.org/2011/content# | Representing Content in RDF |
| co | http://purl.org/ontology/co/core# | Counter Ontology |
| coll | http://swan.mindinformatics.org/ontologies/1.2/collections/ | Collections Ontology |
| con | http://www.w3.org/2000/10/swap/pim/contact# | Contact |
| coo | http://purl.org/coo/ns# | Car Options Ontology |
| coun | http://www.daml.org/2001/09/countries/iso-3166-ont# | ISO 3166 Country Codes |
| crm | http://purl.org/NET/cidoc-crm/core# | CIDOC Conceptual Reference Model |
| crsw | http://courseware.rkbexplorer.com/ontologies/courseware# | ReSIST Courseware Ontology |
| cs | http://purl.org/vocab/changeset/schema# | Changeset |
| ctag | http://commontag.org/ns# | Common Tag Vocabulary |
| ctorg | http://purl.org/ctic/infraestructuras/organizacion# | Vocabulario de la estructura de organismos públicos |
| dady | http://purl.org/NET/dady# | Dataset Dynamics (dady) vocabulary |
| daia | http://purl.org/ontology/daia/ | Document Availability Information Ontology |
| dc | http://purl.org/dc/terms/ | DCMI Metadata Terms |
| dcam | http://purl.org/dc/dcam/ | DCMI Abstract Model |
| dcat | http://www.w3.org/ns/dcat# | Data Catalog Vocabulary |
| dce | http://purl.org/dc/elements/1.1/ | Dublin Core Metadata Element Set |
| dcite | http://purl.org/spar/datacite/ | The DataCite Ontology |
| dcndl | http://ndl.go.jp/dcndl/terms/ | NDL Metadata Terms |
| dctype | http://purl.org/dc/dcmitype/ | DCMI Type Vocabulary |
| deo | http://purl.org/spar/deo/ | The Discourse Elements Ontology |
| dir | http://schemas.talis.com/2005/dir/schema# | Directory Schema |
| dl | http://www.loa-cnr.it/ontologies/DOLCE-Lite.owl# | The DOLCE and DnS ontologies in OWL |
| doac | http://ramonantonio.net/doac/0.1/ | Description of a Career |
| doap | http://usefulinc.com/ns/doap# | Description of a Project vocabulary |
| doc | http://www.w3.org/2000/10/swap/pim/doc# | Works, licences, derivatives and dependencies |
| doco | http://purl.org/spar/doco/ | DoCO, the Document Components Ontology |
| dqm | http://purl.org/dqm-vocabulary/v1/dqm# | The Data Quality Management Vocabulary |
| dr | http://purl.org/swan/2.0/discourse-relationships/ | Discourse relationships vocabulary |
| ds | http://purl.org/ctic/dcat# | Dataset Catalog Vocabulary |
| dul | http://www.loa-cnr.it/ontologies/DUL.owl# | DOLCE+DnS Ultralite |
| ecos | http://kmm.lboro.ac.uk/ecos/1.0# | Enterprise Competence Organisation Schema |
| edm | http://www.europeana.eu/schemas/edm/ | Europeana Data Model vocabulary |
| ends | http://labs.mondeca.com/vocab/endpointStatus# | Vocabulary of endpoint status (availability, responseTime) |
| ep | http://eprints.org/ontology/ | EPrints Ontology |
| event | http://purl.org/NET/c4dm/event.owl# | The Event Ontology |
| ex | http://purl.org/net/ns/ex# | Example vocabulary |
| exif | http://www.w3.org/2003/12/exif/ns# | Exif data description vocabulary |
| fabio | http://purl.org/spar/fabio/ | FRBR-aligned Bibliographic Ontology |
| foaf | http://xmlns.com/foaf/0.1/ | Friend of a Friend vocabulary |
| frbr | http://purl.org/vocab/frbr/core# | Expression of Core FRBR Concepts in RDF |
| frbre | http://purl.org/vocab/frbr/extended# | Extended FRBR |
| gastro | http://www.ebsemantics.net/gastro# | ebSemantics Gastro Ontology |
| gc | http://www.oegov.org/core/owl/gc# | oeGOV Government Core Ontology |
| geo | http://www.w3.org/2003/01/geo/wgs84_pos# | WGS84 Geo Positioning |
| geof | http://www.mindswap.org/2003/owl/geo/geoFeatures20040307.owl# | Geo Features |
| geop | http://aims.fao.org/aos/geopolitical.owl# | FAO Geopolitical Ontology |
| geos | http://www.telegraphis.net/ontology/geography/geography# | Geographis Ontology |
| geosp | http://rdf.geospecies.org/ont/geospecies# | GeoSpecies Ontology |
| gn | http://www.geonames.org/ontology# | The Geonames Ontology |
| gnm | http://www.geonames.org/ontology/mappings_v3.01.rdf | Geonames mappings |
| gr | http://purl.org/goodrelations/v1# | The GoodRelations Ontology for Semantic Web-based E-Commerce |
| grddl | http://www.w3.org/2003/g/data-view# | Gleaning Resource Descriptions from Dialects of Languages Vocabulary |
| gso | http://www.w3.org/2006/gen/ont# | Generic Specific Ontology |
| hr | http://www.wsmo.org/ns/hrests# | hRESTS Ontology |
| http | http://www.w3.org/2011/http# | HTTP in RDF |
| ical | http://www.w3.org/2002/12/cal/icaltzd# | iCalendar |
| inno | http://purl.org/innovation/ns# | Ontology for Innovation |
| interval | http://reference.data.gov.uk/def/intervals/ | Intervals Ontology |
| irw | http://www.ontologydesignpatterns.org/ont/web/irw.owl# | The Identity of Resources on the Web ontology |
| is | http://purl.org/ontology/is/core# | Info Service Ontology |
| itsmo | http://ontology.it/itsmo/v1# | IT Service Management Ontology |
| kdo | http://kdo.render-project.eu/kdo# | The Knowledge Diversity Ontology |
| keys | http://purl.org/NET/c4dm/keys.owl# | Keys Ontology |
| label | http://purl.org/net/vocab/2004/03/label# | label |
| lcy | http://purl.org/vocab/lifecycle/schema# | Lifecycle Schema |
| leo | http://linkedevents.org/ontology/ | Linking Open Descriptions of Events |
| lexinfo | http://www.lexinfo.net/lexinfo# | LEXINFO Vocabulary |
| lgdo | http://linkedgeodata.org/ontology/ | LinkedGeoData ontology |
| lingvo | http://www.lingvoj.org/ontology# | Lingvoj Ontology |
| lmf | http://www.lexinfo.net/lmf# | Lexical Markup Framework Ontology |
| loc | http://purl.org/ctic/infraestructuras/localizacion# | Vocabulario de Localizaciones |
| loted | http://www.loted.eu/ontology# | LOTED ontology |
| lvont | http://lexvo.org/ontology# | Lexvo.org Ontology |
| mads | http://www.loc.gov/mads/rdf/v1# | Metadata Authority Description Schema |
| meb | http://rdf.myexperiment.org/ontologies/base/ | The myExperiment Base Ontology |
| mo | http://purl.org/ontology/mo/ | Music Ontology |
| moat | http://moat-project.org/ns# | Meaning of a Tag Ontology |
| mrel | http://id.loc.gov/vocabulary/relators/ | MARC Code List for Relators |
| msm | http://cms-wg.sti2.org/ns/minimal-service-model# | Minimal Service Model |
| msr | http://www.telegraphis.net/ontology/measurement/measurement# | Measurement Ontology |
| muto | http://purl.org/muto/core# | Modular Unified Tagging Ontology (MUTO) |
| nfo | http://www.semanticdesktop.org/ontologies/2007/03/22/nfo# | NEPOMUK File Ontology |
| ngeo | http://geovocab.org/geometry# | NeoGeo Geometry Ontology |
| ntag | http://ns.inria.fr/nicetag/2010/09/09/voc# | Nice Tag Ontology |
| oan | http://data.lirmm.fr/ontologies/oan/ | Ontologie de l'Assemblée Nationale |
| obsm | http://rdf.geospecies.org/methods/observationMethod# | Observation Method Ontology |
| ogp | http://ogp.me/ns# | Open Graph Protocol Vocabulary |
| olo | http://purl.org/ontology/olo/core# | Ordered List Ontology |
| ont | http://purl.org/net/ns/ontology-annot# | Ontology annotation DLiser vocabulary |
| ontopic | http://www.ontologydesignpatterns.org/ont/dul/ontopic.owl# | Ontopic Ontology |
| openvoc | http://open.vocab.org/terms/ | OpenVocab |
| opmv | http://purl.org/net/opmv/ns# | Open Provenance Model Vocabulary |
| opo | http://online-presence.net/opo/ns# | Online Presence Ontology |
| opus | http://lsdis.cs.uga.edu/projects/semdis/opus# | SwetoDblp Ontology of Computer Science Publications |
| ordf | http://purl.org/NET/ordf/ | ORDF Vocabulary |
| ore | http://www.openarchives.org/ore/terms/ | The OAI ORE terms vocabulary |
| org | http://www.w3.org/ns/org# | Core organization ontology |
| organog | http://reference.data.gov.uk/def/organogram/ | Organogram Data Vocabulary |
| osadm | http://data.ordnancesurvey.co.uk/ontology/admingeo/ | The administrative geography and civil voting area ontology |
| osspr | http://data.ordnancesurvey.co.uk/ontology/spatialrelations/ | Spatial Relations Ontology |
| ostop | http://www.ordnancesurvey.co.uk/ontology/Topography/v0.1/Topography.owl# | Ordnance Survey Topography Ontology |
| parl | http://reference.data.gov.uk/def/parliament/ | Parliament Ontology |
| part | http://purl.org/vocab/participation/schema# | Participation Schema |
| passim | http://data.lirmm.fr/ontologies/passim# | PASSIM ontology |
| pav | http://swan.mindinformatics.org/ontologies/1.2/pav/ | Provenance, Authoring and Versioning Ontology Specification |
| pay | http://reference.data.gov.uk/def/payment# | Payments ontology |
| pbo | http://purl.org/ontology/pbo/core# | Play Back Ontology |
| pc | http://purl.org/procurement/public-contracts# | Public Contracts Ontology |
| pdo | http://ontologies.smile.deri.ie/pdo# | Project Documents Ontology |
| pna | http://data.press.net/ontology/asset/ | Press.net Asset Ontology |
| pnc | http://data.press.net/ontology/classification/ | Press.net Classification Ontology |
| pne | http://data.press.net/ontology/event/ | Press.net Event Ontology |
| pns | http://data.press.net/ontology/stuff/ | Press.net Stuff Ontology |
| pnt | http://data.press.net/ontology/tag/ | Press.net Tag Ontology |
| po | http://purl.org/ontology/po/ | Programmes ontology |
| prel | http://www.perceive.net/schemas/relationship/ | Relationships Schema |
| premis | http://multimedialab.elis.ugent.be/users/samcoppe/ontologies/Premis/premis.owl# | PREMIS Ontology |
| prkm | http://proton.semanticweb.org/2005/04/protonkm# | PROTON Knowledge Management Ontology |
| pro | http://purl.org/spar/pro/ | The Publishing Roles Ontology |
| prov | http://purl.org/net/provenance/ns# | Provenance Vocabulary Core Ontology |
| prv | http://purl.org/ontology/prv/core# | Property Reification Vocabulary |
| prvt | http://purl.org/net/provenance/types# | Provenance Vocabulary types |
| pso | http://purl.org/spar/pso/ | The Publishing Status Ontology |
| psys | http://proton.semanticweb.org/2005/04/protons# | PROTON (Proto Ontology), System Module |
| ptop | http://proton.semanticweb.org/2005/04/protont# | PROTON (Proto Ontology), Top Module |
| pupp | http://proton.semanticweb.org/2005/04/protonu# | PROTON (Proto Ontology), Upper module |
| pwo | http://purl.org/spar/pwo/ | The Publishing Workflow Ontology |
| qb | http://purl.org/linked-data/cube# | The data cube vocabulary |
| qudt | http://qudt.org/schema/qudt# | Quantities, Units, Dimensions and Types |
| r2rml | http://www.w3.org/ns/r2rml# | RDB to RDF Mapping Language Schema |
| rdfg | http://www.w3.org/2004/03/trix/rdfg-1/ | Graph |
| rec | http://purl.org/ontology/rec/core# | Recommendation Ontology |
| rel | http://purl.org/vocab/relationship/ | Relationship |
| rev | http://purl.org/stuff/rev# | Review Vocabulary |
| rss | http://purl.org/rss/1.0/ | Vocabulary for Rich Site Summary (RSS) 1.0 |
| ru | http://purl.org/imbi/ru-meta.owl# | Representational Units Metadata Ontology |
| sao | http://salt.semanticauthoring.org/ontologies/sao# | SALT Annotation Ontology |
| sc | http://purl.org/science/owl/sciencecommons/ | Science Commons |
| schema | http://schema.org/ | The schema.org terms in RDFS+OWL |
| scip | http://lod.taxonconcept.org/ontology/sci_people.owl# | Scientific People Ontology |
| scovo | http://purl.org/NET/scovo# | The Statistical Core Vocabulary |
| sd | http://www.w3.org/ns/sparql-service-description# | SPARQL 1.1 Service Description |
| sdmx | http://purl.org/linked-data/sdmx# | SDMX-RDF vocabulary |
| sdo | http://salt.semanticauthoring.org/ontologies/sdo# | SALT Document Ontology |
| semio | http://www.lingvoj.org/semio# | Semio, an ontology of signs |
| sim | http://purl.org/ontology/similarity/ | The Similarity Ontology |
| sioc | http://rdfs.org/sioc/ns# | Semantically-Interlinked Online Communities |
| skos | http://www.w3.org/2004/02/skos/core# | Simple Knowledge Organization System |
| socsv | http://purl.org/NET/schema-org-csv# | Schema.org CSV |
| sp | http://data.lirmm.fr/ontologies/sp# | Ontologie du Service Public |
| spatial | http://geovocab.org/spatial# | NeoGeo Spatial Ontology |
| sport | http://purl.org/ontology/sport/ | Sport Ontology |
| sro | http://salt.semanticauthoring.org/ontologies/sro# | SALT Rhetorical Ontology |
| stories | http://purl.org/ontology/stories/ | Stories Ontology |
| swc | http://data.semanticweb.org/ns/swc/ontology# | Semantic Web Conference Ontology |
| swp | http://www.w3.org/2004/03/trix/swp-1/ | Graph Authority |
| swpo | http://sw-portal.deri.org/ontologies/swportal# | Semantic Web Portal Ontology |
| swrc | http://swrc.ontoware.org/ontology# | Semantic Web for Research Communities |
| swrl | http://www.w3.org/2003/11/swrl# | Semantic Web Rule Language |
| tac | http://ns.bergnet.org/tac/0.1/triple-access-control# | TripleAccessControl Ontology |
| tag | http://www.holygoat.co.uk/owl/redwood/0.1/tags/ | Tag ontology |
| thea | http://purl.org/theatre# | Theatre Ontology |
| time | http://www.w3.org/2006/time# | Time Ontology |
| tio | http://purl.org/tio/ns# | The Tickets Ontology |
| tl | http://purl.org/NET/c4dm/timeline.owl# | The Timeline Ontology |
| tmo | http://www.w3.org/2001/sw/hcls/ns/transmed/tmo# | Translational Medicine Ontology |
| transit | http://vocab.org/transit/terms/ | TRANSIT |
| turismo | http://idi.fundacionctic.org/cruzar/turismo# | Ontología de Turismo para el Ayuntamiento de Zaragoza |
| txn | http://lod.taxonconcept.org/ontology/txn.owl# | TaxonConcept Ontology |
| tzont | http://www.w3.org/2006/timezone# | Time Zone Ontology |
| umbel | http://umbel.org/umbel# | Upper Mapping and Binding Exchange Layer |
| unpc | http://purl.uniprot.org/core/ | Uniprot Core Ontology |
| user | http://schemas.talis.com/2005/user/schema# | User Schema |
| vaem | http://www.linkedmodel.org/schema/vaem# | Vocabulary for Attaching Essential Metadata |
| vann | http://purl.org/vocab/vann/ | VANN: A vocabulary for annotating vocabulary descriptions |
| vcard | http://www.w3.org/2006/vcard/ns# | An Ontology for vCards |
| vdpp | http://data.lirmm.fr/ontologies/vdpp# | Vocabulary for Dataset Publication Projects |
| vivo | http://vivoweb.org/ontology/core# | VIVO Core Ontology |
| voaf | http://labs.mondeca.com/vocab/voaf# | Vocabulary of a Friend |
| voag | http://voag.linkedmodel.org/schema/voag# | Vocabulary Of Attribution and Governance |
| void | http://rdfs.org/ns/void# | Vocabulary of Interlinked Datasets |
| vs | http://www.w3.org/2003/06/sw-vocab-status/ns# | SemWeb Vocab Status ontology |
| vso | http://purl.org/vso/ns# | Vehicle Sales Ontology |
| vvo | http://purl.org/vvo/ns# | Volkswagen Vehicles Ontology |
| wdrs | http://www.w3.org/2007/05/powder-s# | Protocol for Web Description Resources |
| whois | http://www.kanzaki.com/ns/whois# | Who's who description vocabulary |
| wi | http://purl.org/ontology/wi/core# | The Weighted Interests Vocabulary |
| wlo | http://purl.org/ontology/wo/ | Wildlife Ontology |
| wo | http://purl.org/ontology/wo/core# | Weighting Ontology |
| wot | http://xmlns.com/wot/0.1/ | Web Of Trust |
| wsl | http://www.wsmo.org/ns/wsmo-lite# | WSMO-Lite Ontology |
| xl | http://www.w3.org/2008/05/skos-xl# | SKOS eXtension for Labels |