Refers to a circus clown or a comedic performer in a similar role. Often associated with the loanword ピエロ, but 道化師 carries a slightly more traditional or theatrical nuance.
See also: ピエロ
The clown made the children laugh at the circus.
He plays a clown on stage.
道化師 is a more formal or literary term for a clown, while ピエロ is the everyday word for the same circus performer.
Compound of 道化 (dōke, 'buffoonery') + 師 (shi, 'master, specialist'). The exact historical derivation is uncertain, but the word has been used since at least the Edo period to refer to comedic performers.