onanism
/ˈəʊnənɪz(ə)m
/noun [mass noun] formal
1Masturbation.
2Coitus interruptus.
Derivatives
onanist
/ nounonanistic
Origin
Early 18th century: from French onanisme or modern Latin onanismus, from the name Onan (Gen. 38:9), who practised coitus interruptus.