crotch

Concise Oxford English Dictionary © 2008 Oxford University Press:
crotch/krɒtʃ/

▶noun

• 1 the part of the human body between the legs where they join the torso.

• 2 a fork in a tree, road, or river.

– derivatives
crotched adjective,
crotchless adjective.

– origin C16: perh. rel. to OFr. croche ‘shepherd's crook’, based on ON krókr ‘hook’; partly also a var. of crutch.