Why do we say “grammatically” instead of “grammarically”?

Question

My son said the word “grammarically”, and I corrected him that the word is actually “grammatically”. He asked why that’s the case since it’s referencing grammar and not grammat. I could not find the answer via google. Please help.

In: Other

Answer 1

Because English is weird and borrows and steals from wherever it can. The etymology of the word is from Greek, “gramma” (letter) to “gramatike techne” (art of letters) and while the noun came to English from French “grammaire” the adjective reflects, correctly, the Greek adjective root.