"playing the clown," 1848, verbal noun from clown (v.).
Entries linking to clowning
clown v.
c. 1600, "to play the clown onstage," from clown (n.); colloquial sense of "to behave inappropriately" (as in clown around, 1932) is attested by 1928, perhaps from the theatrical slang sense of "play a (non-comical) part farcically or comically" (1891). Related: Clowned; clowning.