semantics

from The American Heritage® Dictionary of the English Language, 5th Edition.

• noun The study or science of meaning in language.
• noun The competence of a speaker with regard to the interpretation of the meaning of linguistic structures.
• noun The study of relationships between signs and symbols and what they represent.
• noun The meaning or the interpretation of a word, sentence, or other language form.

from The Century Dictionary.

• noun That branch of philology which is concerned with the meanings of words and the development of meanings; semasiology.

from the GNU version of the Collaborative International Dictionary of English.

• the study of the meanings of words and of the sense development of words; -- formerly called semasiology.
• a doctrine and philosophical approach to language and its relationship to thought and behavior, developed by Alfred Korzybski (1879-1950), which holds that the capacity to express ideas and thereby improve one's interaction with others and one's environment is enhanced by training in the more critical use of words and other symbols; -- also called general semantics.
• the meanings of words as they are used to achieve an effect; especially, the multiple meanings of words or the multiplicity of words having the same meaning; -- used in referring to the confusion that can be caused (intentionally or unintentionally) by multiple meanings.

from Wiktionary, Creative Commons Attribution/Share-Alike License.

• noun linguistics A branch of linguistics studying the meaning of words.
• noun The study of the relationship between words and their meanings.
• noun The individual meanings of words, as opposed to the overall meaning of a passage.

from WordNet 3.0 Copyright 2006 by Princeton University. All rights reserved.

• noun the study of language meaning
• noun the meaning of a word, phrase, sentence, or text