Princeton's WordNet

1. proficiency(noun)

   the quality of having great facility and competence

2. proficiency, technique(noun)

   skillfulness in the command of fundamentals deriving from practice and familiarity

   "practice greatly improves proficiency"

Kernerman English Learner's Dictionary

1. proficiency(noun)əˈfɪʃ ənt

   a good level of ability, skill, etc.

   All teachers must demonstrate proficiency in math.

Wiktionary

1. proficiency(Noun)

   Ability, skill, competence.

2. proficiency(Noun)

   Knowledge.

Origin: From proficientem, from proficere.

Webster Dictionary

1. Proficiency(noun)

   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

• vaardigheidAfrikaans
• بَراعَه، مَهارَه، حِذْقArabic
• вещинаBulgarian
• competênciaPortuguese (BR)
• odbornostCzech
• die TüchtigkeitGerman
• kyndighedDanish
• επάρκεια, ικανότηταGreek
• competencia; suficiencia (examen)Spanish
• pädevusEstonian
• مهارتFarsi
• pätevyysFinnish
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• מְיוּמָנוּתHebrew
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• ความเชี่ยวชาญThai
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