WordNet

WordNet is a lexical database that represents English word senses through synsets connected by labeled relationships. It groups meanings by part of speech, while keeping different meanings of the same written form distinct. Its organization therefore supports queries about concepts rather than spelling alone.^[ref]

For a toy information-retrieval task, suppose an annotated query uses the financial sense of bank. Expanding it with terms attached to a river-margin sense would introduce irrelevant results even though the spelling matches. A sense-aware representation supplies the distinction needed to avoid that error; a separate method still has to choose the intended sense from context.

WordNet also records relations such as hyponymy, connecting more specific concepts to broader ones. Following a labeled relation answers a different question from finding another member of the same synset.^[ref] Neither neighborhood nor shared spelling guarantees that two expressions can replace each other in every sentence.