attitude

Attitude comes from French attitude, borrowed from Italian attitudine, meaning aptness or fitness. That Italian word traces back to Medieval Latin aptitūdō and actitūdō, themselves rooted in the Latin verbs aptō (to fit) and actitō (to act repeatedly).

The facts given don't trace a detailed shift in meaning, only the chain of borrowing from Latin through Medieval Latin, Italian, and French into English.

Attitude is a doublet of aptitude — the two words descend from the same Medieval Latin source, aptitūdō, but arrived in English by different paths.