Floppy part of a beagle

EAR

This body part helps a beagle pick up scents and often flops when they tilt their head curiously.

A beagle’s ears are famously long and floppy, so the clue directly points to that standout feature. The word "floppy" hints at the droopy nature of the ears, making it a straightforward description. Since "ear" is the body part being described, no wordplay or hidden meaning is involved—just a simple, literal reference to a beagle’s most recognizable trait.