A crotch is a part of your body where your legs meet your hips. It's that area between your thighs.
You'll often hear people talk about the crotch when they're referring to pants or underwear that are too tight, riding up into the crotch area and making them uncomfortable. You might also hear someone complaining about an itch in their crotch, which usually means right where the legs meet the hips. Doctors might ask you if you have any discomfort in your crotch, especially for people who've had a certain type of surgery.
The ventral area (very bottom) of the human body between where the legs fork from the torso, in the area of the genitals and anus.
Example: Every mile they rode their crotches felt worse saddlepain.
