Semantics
Semantics is the study of the meaning of words, constructions, and utterances.
Semantics can be divided into two parts: lexical semantics and combination semantics.
Lexical semantics: hypernymy, hyponymy, antonymy, meronymy, holonymy, synonymy, homonymy, polysemy, and homophony.
Compositionality: the meaning of the whole often differs from the meaning of the parts.
Idioms correspond to cases where the compound phrase means something completely different . . from its parts.