master of one

Etymology

• From the phrase "a jack of all trades is a master of none, but better than a master of one"

Noun

Singular master of one

Plural masters of one

1. (idiomatic) (countable) A master of one is someone who is very good at one specific thing and isn't very good at anything else.
   • Antonym: jack of all trades

   Julia can draw incredibly well, but she's terrible at everything else. She's a master of one.