The same will not be said about My Week With Marilyn, no matter how proficient Williams is.
“We clearly have a proficient bombmaker in town,” says a European security official.
More impressive than their appearance were their proficient debating skills.
1580s, back-formation from proficiency or else from Old French proficient (15c.), from Latin proficientem (nominative proficiens), present participle of proficere "to make progress, go forward, effect, accomplish, be useful" (see proficiency). Related: Proficiently.