La mouche

une mouche (pronounced moosh) = a fly, bull's eye (when referring to a target) or a fake beauty spot.

Lots of interesting expressions with mouche:

• il ne ferait pas de mal à une mouche = he wouldn't hurt a fly
• on entendrait une mouche voler = you could hear a pin drop (literally a fly buzz)
• quelle mouche les a piqués? = what's gotten into them? (literally what fly bit them)
• regarder voler les mouches = to stare into space (literally to watch flies)
• prendre la mouche = to get upset, to take something personally
• tomber comme des mouches = to drop like flies.