This document discusses semantics and lexical relations between words. It defines semantics as the study of meaningful units and their cognitive meanings. There are several lexical relations between words based on their senses, including synonymy, homonymy, polysemy, antonymy, and hyponymy. Synonymy refers to words that have the same meaning. Homonymy and polysemy involve ambiguity, where homonymy refers to words that are identical but have different unrelated meanings, while polysemy refers to a word whose meaning is extended metaphorically. Antonymy describes opposites, including complementary, gradable, and relational opposites. Hyponymy describes a subordinate, more specific relationship between a general lexeme and