Dancer
来自Big Physics
Middle English: from Old French dancer (verb), dance (noun), of unknown origin.
wiktionary
From Middle English dauncer, dawncere, dancere, equivalent to dance + -er.
etymonline
dancer (n.)
"one who dances or takes part in a dance," mid-15c., agent noun from dance (v.). As a surname from early 12c. (Godwinus Dancere).