noun
- a person of the ectomorphic type.
noun
- a person with a thin body build: said to be correlated with cerebrotoniaCompare endomorph, mesomorph
1940, coined by Sheldon from ecto- + Greek morphe (see morphine). Related: Ectomorphic.
n.
- An individual having a lean, slightly muscular body build in which tissues derived from the embryonic ectoderm predominate.