grammatically has definitions from the field of grammar
1
[ adverb ] (grammar) in a grammatical manner

Examples

"this child already speaks grammatically"

Used in print

(H. A. Gleason, "Review of African language studies...)

And the more complex the morphophonemic_system is in_relation_to the phonemic base , the less easily a phonemic_system will be analysed without close attention to the morphophonemics - at_least , the less satisfying will a phonemic statement be if it cannot be related through morphophonemic rules to grammatically meaningful structures .

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