Erotic stimulation of one's own genital organs, usually to achieve orgasm.
Masturbatory behavior is common in infants and adolescents, and is indulged in by many adults as well. Studies indicate that over 90% of U.S. males and 60–80% of U.S. females have masturbated at one time or another. Christian moral teaching condemned masturbation as the sin of Onan, who in the Old Testament was censured for spilling his seed, and the Roman Catholic Church still officially condemns it.