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onanism

[oh-nuh-niz-uh m]
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noun

withdrawal of the penis in sexual intercourse so that ejaculation takes place outside the vagina; coitus interruptus.
masturbation.

Origin of onanism

1720–30; after Onan, son of Judah (Gen. 38:9); see -ism
Related formso·nan·ist, nouno·nan·is·tic, adjective
Dictionary.com Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2019

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Historical Examples of onanistic

British Dictionary definitions for onanistic

onanism

noun

another name for masturbation, coitus interruptus
Derived Formsonanist, noun, adjectiveonanistic, adjective

Word Origin for onanism

C18: after Onan, son of Judah; see Genesis 38:9
Collins English Dictionary - Complete & Unabridged 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012
Word Origin and History for onanistic

onanism

n.

"masturbation," also "coitus interruptus," 1727, from Onan, son of Judah (Gen. xxxviii:9), who spilled his seed on the ground rather than impregnate his dead brother's wife: "And Onan knew that the seed should not be his; and it came to pass, when he went in unto his brother's wife, that he spilled it on the ground, lest that he should give seed to his brother." The moral of this verse was redirected by those who sought to suppress masturbation.

Online Etymology Dictionary, © 2010 Douglas Harper
Medicine definitions for onanistic

onanism

[ō′nə-nĭz′əm]

n.

coitus interruptus
Masturbation.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.