- the branch of linguistics concerned with the nature, the structure, and the development and changes of the meanings of speech forms, or with contextual meaning
- the branch of semiotics dealing with relationships of signs and symbols to the things to which they refer, or with referential meaning
- the relationships between signs and symbols and the concepts, feelings, etc. associated with them in the minds of their interpreters; notional meaning
- the meanings of words, specif. in terms of their connotations, subtle distinctions, etc.
Origin of semantics; from semantic, based on French sémantique
noun(used with a sing. or pl. verb)
- Linguistics a. The study or science of meaning in language.b. The competence of a speaker with regard to the interpretation of the meaning of linguistic structures.c. The study of relationships between signs and symbols and what they represent. Also called semasiology.
- The meaning or the interpretation of a word, sentence, or other language form: We're basically agreed; let's not quibble over semantics.
- (linguistics) A branch of linguistics studying the meaning of words. 
- Semantics is a foundation of lexicography.
- The study of the relationship between words and their meanings.
- The individual meanings of words, as opposed to the overall meaning of a passage.
- The semantics of the terms used are debatable.
- The semantics of a single preposition is a dissertation in itself.
semantics - Computer Definition
The study of the meaning of words. A semantic vocabulary is a formal description of the data used in a specific domain such as advertising, physics, real estate, telecom, etc. Contrast with syntax, which governs the structure of a language and the rules pertaining to the actual data. For example, a semantic tag for temperature may be Fahrenheit, but the syntactic values for Fahrenheit may be numeric -60 to +120. See Semantic Web, semantic error and Systemantics.