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pro·fi·cient

(prə-fĭshənt)

adj.

Having or marked by an advanced degree of competence, as in an art, vocation, profession, or branch of learning.

A person who exhibits such competence; an expert.

[Latin prōficiēns, prōficient-, present participle of prōficere, to make progress; see PROFIT.]

pro·ficient·ly adv.

Synonyms: proficient, adept, skilled, skillful, accomplished, expert
These adjectives mean having or showing knowledge, ability, or skill, as in a profession or field of study. Proficient implies an advanced degree of competence acquired through training: is proficient in Greek and Latin.
Adept suggests a natural aptitude improved by practice: became adept at cutting the fabric without using a pattern.
Skilled implies sound, thorough competence and often mastery, as in an art, craft, or trade: a skilled gymnast who won an Olympic medal.
Skillful adds to skilled the idea of natural dexterity in performance or achievement: is skillful in the use of the hand loom.
Accomplished bears with it a sense of refinement after much training and practice: an accomplished violinist who played the sonata flawlessly.
Expert applies to one with consummate skill and command: an expert negotiator who struck a deal between disputing factions.

Indo-European & Semitic Roots Appendices

Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:

Indo-European Roots

Semitic Roots

The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.

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