One of the words that came up last night in the French conversation group was mouchard, which means an informant and various other things. I thought I’d look into it in more detail here.
Mouchard [mu.ʃaʁ] can mean:
- a snitch, grass or tell-tale (police informant) – also known as indic, cafteur or cafard in French
- a bug (hidden microphone)
- a spyhole or peephole
- a tachograph (device that records the distance and time traveled by a vehicle)
- (a piece of) spyware
- a spyplane
- a black box, flight recorder
It comes from mouche (a fly, bullseye, historically: a spy employed by the ancien régime to seek out subversive ideas) and -ard (pejorative suffix), from Middle French mousche (a fly), from Old French m(o)usche (a fly) [source], from Latin musca (a fly, an inquisitive or prying person) , from Proto-Indo-European *mu(s)/*mews- (fly). Words from the same roots include midge in English and Mücke (midge, gnat, crane fly, mosquito) in German [source].
Related words include:
- mouchardage = informing, grassing, ratting
- moucharder = to rat (on), to tell tales
The French word mouchard has also been borrowed into English, and means an undercover investigator or a police spy, especially in a French-speaking country, or an inverted compass hanging above the captain’s bed. The activity of such people is known mouchardism [source].
Other fly-related expressions in French include:
- faire mouche = to hit the bullseye, to come off, to hit home, to hit the nail on the head
- mouche de coche = back-seat driver (person who pretends to be useful by offering unsolicited advice or by running around without actually doing any work)
- pattes de mouche = scrawl, chicken scratch (illegible handwriting)
- prendre la mouche = to get offended, to get in a huff, to fly off the handle [source]
Are there interesting equivalents of mouchard in other languages?







