noun: 1. a person who has special skill or knowledge in some particular field; specialist; authority: a language expert. 2. a person who has extensive skill or knowledge in a particular field. 3. one with the special skill or knowledge representing mastery of a particular subject. adjective: 1. possessing special skill or knowledge; trained by practice; skillful or skilled (often followed by in or at): an expert driver; to be expert at driving a car. 2. pertaining to, coming from, or characteristic of an expert: expert work; expert advice. 3. skillful or knowledgeable. 4. of, involving, or done by an expert: an expert job. 5. having, involving, or displaying special skill or knowledge derived from training or experience. verb: 1. to act as an expert for. 2. to serve as an expert. Military: 1. the highest rating in rifle marksmanship, above that of marksman and sharpshooter. 2. a person who has achieved such a rating. Obsolete: experienced. Examples: She was an acknowledged expert on child development. an expert at planning dinner parties. Related Words: adroit, experienced, deft, skillful, skilled, adept, trained, professional, authority, artist, crackerjack, crack, slick, virtuoso, savvy, sharp, handy, connoisseur, phenomenon, ace. dexterous. Synonyms: connoisseur, master. experienced, proficient, dexterous. (Noun) ace, adept, artist, authority, cognoscente, connoisseur, crackerjack (also crackajack), dab [chiefly British], dab hand [chiefly British], fiend, geek, guru, hand, hotshot, maestro, master, maven (also mavin), meister, past master, proficient, scholar, shark, sharp, virtuoso, whiz, wizard. (Adjective) adroit, artful, bravura, deft, delicate, dexterous (also dextrous), masterful, masterly, practiced (also practised), skillful, virtuoso, workmanlike. Antonyms: (Noun) amateur, inexpert, nonexpert. (Adjective) amateur, amateurish, artless, rude, unprofessional, unskillful. Synonym Study 1: Skillful, skilled, expert refer to readiness and adroitness in an occupation, craft, or art. Skillful suggests especially adroitness and dexterity: a skillful watchmaker. Skilled implies having had long experience and thus having acquired a high degree of proficiency: not an amateur but a skilled worker. Expert means having the highest degree of proficiency; it may mean much the same as skillful or skilled, or both: expert workmanship. Synonym Study 2: 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: proficient in translating foreign languages. Adept implies special aptitude as well as proficiency: adept at doing long division. Skilled stresses mastery of technique: a skilled surgeon. Skillful implies individual dexterity in execution or performance: skillful drivers. Expert implies extraordinary proficiency and often connotes knowledge as well as technical skill: expert in the evaluation of wines. Origin: 1325–75; Middle English (adj.) < Latin expertus, past participle of experīrī to try, experience. C14: from Latin expertus known by experience, from experīrī to test; see experience. First Known Use: Noun: 1535. Adjective: 14th century. Verb: circa 1889. History and Etymology: Noun: borrowed from French, going back to Middle French, derivative of expert expert entry 2. Adjective: Middle English, borrowed from Anglo-French, borrowed from Latin expertus "tested, shown to be true," from past participle of experīrī "to put to the test, attempt, have experience of, undergo" — more at experience entry 1. Verb: derivative of expert entry 1. Source 1, Source 2.