This document discusses sense relations in language. It defines sense relations as any relation between lexical units in terms of their meaning. Sense relations can be classified into two types: those expressing identity between meanings and those expressing opposition or exclusion. Relations of inclusion and identity include synonymy, homonymy, polysemy and hyponymy. Antonymy is provided as an example of a sense relation expressing opposition between meanings. Other sense relations discussed include paraphrase, homographs, entailment and contradiction.