https://en.wikipedia.org/wiki/Pierrot
From the Wikipedia entry...
*His character in contemporary popular culture—in poetry, fiction, and the visual arts, as well as works for the stage, screen, and concert hall—is that of the sad clown [...]*
A modern "Pierrot" style clown is:
https://en.wikipedia.org/wiki/Puddles_Pity_Party
I have to admit... I wouldn't know about the Pierrot style of clown if it wasn't for Puddles...
https://www.youtube.com/watch?v=Cf1w5GUturU