The Collaborative International Dictionary
Proficience
Proficience \Pro*fi"cience\, Proficiency \Pro*fi"cien*cy\, n. The quality of state of being proficient; advance in the acquisition of any art, science, or knowledge; progression in knowledge; improvement; adeptness; as, to acquire proficiency in music.
Wiktionary
proficience
n. (alternative form of proficiency English)