Grammar (linguistics)[r]: The structural rules that govern the composition of sentences, phrases, and words in any language; alternatively, the system of language itself, i.e. the principles common to all languages. [e]
Linguistic prescriptivism[r]: The laying down or prescribing of normative rules for the use of a language, or the making of recommendations for effective language usage. [e]
Grammar and spell checker[r]: A program, or part of a program, that attempts to verify written text for grammatical correctness and misspelled words. [e]