Origin of ectomorph

First recorded in 1935–40; ecto- + -morph Unabridged Based on the Random House Unabridged Dictionary, © Random House, Inc. 2018

British Dictionary definitions for ectomorph


  1. a person with a thin body build: said to be correlated with cerebrotoniaCompare endomorph, mesomorph
Derived Formsectomorphic, adjectiveectomorphy, noun
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 ectomorph

1940, coined by Sheldon from ecto- + Greek morphe (see morphine). Related: Ectomorphic.

Online Etymology Dictionary, © 2010 Douglas Harper

ectomorph in Medicine


  1. An individual having a lean, slightly muscular body build in which tissues derived from the embryonic ectoderm predominate.
Related formsec′to•morphic adj.ecto•mor′phy n.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.