This is the 3050th most frequent French word.
mouche
Fly (insect).
In this sentence, 'mouche' refers to the insect known as a fly.
Une mouche se pose sur la table.
A fly lands on the table.
Here, 'prendre la mouche' is an idiomatic expression meaning to take offense or get upset quickly.
Il a pris la mouche pour une remarque innocente.
He got upset over an innocent remark.
In this context, 'mouche' refers to an ornamental beauty spot worn as a fashion accessory in certain historical contexts.