noun /ˌtɚməˈnɒləʤi,ˌtɚməˈnɑləʤi/
a) The doctrine of terms; a theory of terms or appellations; a treatise on terms, a system of specialized terms.
b) The set of terms actually used in any business, art, science, or the like; nomenclature; technical terms; as, the terminology of chemistry.
Wikipedia foundation.