InterLex (https://interlex.org) is a dynamic lexicon, initially built on the foundation of NeuroLex (PMID: 24009581), of biomedical terms and common data elements designed to help improve the way that biomedical scientists communicate about their data, so that information systems like the Neuroscience Information Framework (neuinfo.org) and the the Stimulating Peripheral Activity to Relieve Conditions (SPARC) can find data more easily and provide more powerful means of integrating data across distributed resources and datasets. One of the challenges for data integration and FAIR data (Findable, Accessible, Interoperable and Reusable) is the inconsistent use of terminology and data elements. InterLex allows for the association of data fields and data values to common data elements and terminologies enabling the crowdsourcing of data-terminology mappings within and across communities. InterLex provides a stable layer on top of the many other existing terminologies, lexicons, ontologies, and common data element collections and provides a set of inter-lexical and inter-data-lexical mappings.