The Ontology Lookup Service (OLS) is a repository for biomedical ontologies that aims to provide a single point of access to the latest ontology versions. The user can browse the ontologies through the website as well as programmatically via the OLS API.
The OLS provides a web service interface to query multiple ontologies from a single location with a unified output format.The OLS can integrate any ontology available in the Open Biomedical Ontology (OBO) format. The OLS is an open source project hosted on Google Code.