boob

Concise Oxford English Dictionary © 2008 Oxford University Press:
boob1 informal

▶noun

• 1 Brit. an embarrassing mistake.

• 2 N. Amer. a stupid person.

▶verb Brit. make an embarrassing mistake.

– origin early 20th cent.: abbrev. of booby1.

Concise Oxford English Dictionary © 2008 Oxford University Press:
boob2

▶noun informal a woman's breast.

– origin 1950s: abbrev. of booby2.