Pubic hair
Pubic hair appears during puberty in girls and boys. The onset of pubic hair development is termed pubarche. In developed countries, this usually happens around the age of ten in girls and around the age of eleven or twelve in boys. Beginning with only a few hairs above the vulva (in girls) or penis (in boys), the area quickly fills out in a triangular shape, making a thick patch of hair. In boys, the patch becomes a trapezoid shape, meaning four-sided.