proficient, adept, skilled, skillful, expert mean having great knowledge and experience in a trade or profession. proficient implies a thorough competence derived from training and practice.

(Definition of proficient from the Cambridge Academic Content Dictionary © Cambridge University Press)

PROFICIENT definition: well-advanced or competent in any art, science, or subject; skilled. See examples of proficient used in a sentence.

We got very proficient at sweeping them out of the way with rakes so we didn't step on them.

Definition of proficient adjective in Oxford Advanced Learner's Dictionary. Meaning, pronunciation, picture, example sentences, grammar, usage notes, synonyms and more.

WordReference Random House Unabridged Dictionary of American English © 2025 pro•fi•cient (prə fish′ ənt), adj. well-advanced or competent in any art, science, or subject; skilled: a proficient swimmer. n. …

1. fully competent in any art, science, or subject; skilled: a proficient swimmer. n. 2. an expert.

When someone has become good at something, they are proficient. After all those hours playing video games, you must be very proficient at them. Proficient comes from the Latin for making progress, so …

There are five meanings listed in OED's entry for the word proficient, three of which are labelled obsolete. See ‘Meaning & use’ for definitions, usage, and quotation evidence.

He has become very proficient at computer programming. She is proficient in two foreign languages. He shows a high level of proficiency in Spanish.