The "hard gainer" of the fitness world since they have a hard time building muscle although it is not impossible.

They're naturally small built with long, lightly muscular limbs. The have a fast metabolism so the can stuff their faces without putting on weight.

To gain muscle they need to eat alot and do heavy weight training, its advised that they avoid cardiovascular activities since cardiovascular activities burn fat
Examples of ectomorphs are Lisa Kudrow, Kate Moss, Brad Pitt, Seth Green, Edward Norton and most NBA players
by Malloy91 September 7, 2008
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An individual having a lean, slightly muscular body build in which tissues derived from the embryonic ectoderm predominate.
"Steve Urkel is an ectomorph."
by Mesomorph January 13, 2004
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An individual who has a lean, muscular physique without having to workout his or her body.
Brad Pitt, Jake Gyllenhaal, and Quenton So are all examples of male ectomorphs.
by Teela January 16, 2007
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Scrawny individual who has a difficult time putting on mass or gaining weight. Often used as a condescending term among weight-lifters to describe skinny, and thereby weaker, males. In the bodybuilding terminology, the antonym of ectomorph is endomorph - which is a fatter or heavier set individual who conversely has a difficult time losing weight.
Kevin: Look at that ectomorph over there Keith, he's about as skinny as a twig!
Keith: Yeah I would help him out, but I don't care. He can do whatever the F**K he wanna do!
by hodgetwins June 30, 2013
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An individual who has a lean, muscular physique without having to workout his or her body.
Quenton is an example of a male ectomorph.
by teela January 22, 2007
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'Ectomorph' traditionally refers to a person who has a fast metabolism and little fat. However, it is more commonly used by those who have little muscle as an excuse. Many skinny people would call themselves 'ectomorphs' or 'hardgainers' but in actual fact they just don't eat enough.
Female: Ewww, why are you so skinny?
Insecure Male: Its because of my genetics. I'm an ectomorph!
by 1N50MN1UM November 11, 2012
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thin body long thin limbs feet hands short torsos long slender necks

doesnt really eat much
gorgeous sexy women with small shoulders and long sexy thin leggz

eats anything no weigth gain

like me!
by caitlyn January 1, 2005
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