When someone tries to take credit for another's work, a sharp public rebuke can be a flea in one's ear.

If one misses practice, one can expect fleas in one's ear from the coach.

The garden guide explained how the eight-spotted flea beetle feeds on young spinach leaves, often leaving telltale shot-hole damage.

My grandmother always told me that if you lie with dogs you will get fleas, so choose your friends carefully.

He ignored the warnings and, as his friends pointed out, if you lie down with dogs, you get up with fleas.