Simple Definition of expert

from our Learner's Dictionary

expert

1 of 2

noun

plural experts
: a person who has special skill or knowledge relating to a particular subject
a computer expert
She was an acknowledged expert on/in child development.
an expert at planning dinner parties

expert

2 of 2

adjective

: having or showing special skill or knowledge because of what you have been taught or what you have experienced
We received some expert advice.
an expert poker player
an expert opinion
The company has become expert at/in adapting its products for new clients.
expert testimony
an expert witness [=a witness in a court of law who is an expert on a particular subject]

Cite this Entry

“Expert.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/expert. Accessed 15 Apr. 2026.

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