Grammatical
Pronunciation : Gram*mat"ic*al
Part of Speech : a.
Etymology : [L. grammaticus, grammaticalis; Gr. grammatical. See Grammar.]
Definition : 1. Of or pertaining to grammar; of the nature of grammar; as, a grammatical rule.
2. According to the rules of grammar; grammatically correct; as, the sentence is not grammatical; the construction is not grammatical. -- Gram*mat"ic*al*ly, adv. -- Gram*mat"ic*al*ness, n.
Source : Webster's Unabridged Dictionary, 1913