DECEASED FACE

I had always wondered about the etymology of deadpanning (the action of saying something funny while keeping a straight face), but for some reason never thought to look it up until now. The term first showed up as a two-word adjective in 1920s, emerging as a slang word in the acting industry and spreading from there. Although its origins haven't been recorded anywhere, it seems that the "dead" part is just analogous to "expressionless" and pan was a colloquial word for "face", due to a similarity with the flatness of the cooking tool. So deadpanning is just keeping an "expressionless face", which checks out pretty well with the modern definition. According to Google NGrams, usage of deadpan has increased with its increased exposure in American comedy, peaking in usage in 2017.