The part of linguistics that is concerned with the structure of language is divided into a number of subfields: Phonetics - the study of speech sounds in their physical aspects. Phonology - the study of speech sounds in their cognitive aspects. Morphology - the study of the formation of words. Does this help at all?
The answer is linguistics. It deals with studying languages in its form, meaning and context. It also determines how it is transmitted and understood by people who use them. It also determines how a word gets its meaning and its origins.
