corticosteroid (n.)

"steroid isolated from the adrenal cortex," 1941, from cortico-, combining form of Latin cortex (genitive corticis) "bark of a tree," in modern anatomy applied to enveloping parts or surfaces (see corium).

naturally occuring substance based on a carbon skeleton similar to that of sterol molecules, 1936, from sterol + -oid "resembling." Related: Steroids.