A female, typically one with small
breasts. (Often used in a negative context.)
Males may be called chestlets as an insult, much like calling a
male a "little girl". (Also, may be a more demeaning insult than "
manlet".)
"I
don't see how anyone can like chestlets, more
meat on a woman is better!"
"Shut up, you chestlet."
"Forget that slag, she's a chestlet anyway, not worth your
time."