From the free online dictionary:
Meaning of logic
Spelled Pronunciation [loj-ik]
Logic is a noun
1. the science that investigates the principles governing correct or reliable inference.
2. a particular method of reasoning or argumentation: We were unable to follow his logic.
3. the system or principles of reasoning applicable to any branch of knowledge or study.
4. reason or sound judgment, as in utterances or actions: There wasn't much logic in her move.
5. convincing forcefulness; inexorable truth or persuasiveness: the irresistible logic of the facts.
6. Computers. logic circuit.
Origin:
1325–75; ME logik < L logica, n. use of neut. pl. (in ML taken as fem. sing.) of Gk logikós of speech or reason. See logo-, -ic
Synonyms:
sense, cogency.