Pet-de-loup is French slang for a ridiculous old academic, in traffic from the mid-nineteenth to early twentieth century. Literally means wolf fart.
Two instances of use:
One of the pieces in Rene Georges Hermann-Paul
's 1919 woodcut series La danse macabre; vingt gravures sur bois
is titled "Le Pet-de-Loup" and depicts shadowy professorial figures before a blackboard. This
blog includes an image.
Ezra Pound deploys the term in his typical macaronic fashion in Canto XIV:
pets-de-loup, sitting on piles of stone books,
obscuring the texts with philology,
hiding them under their persons,