cor•ti•co•ster•oid(kôr′tə kō ster′oid, -stēr′-),USA pronunciationn.[Biochem.]any of a class of steroids, as aldosterone, hydrocortisone, or cortisone, occurring in nature, esp. as a product of the adrenal cortex, or synthesized. Also called cor•ti•coid(kôr′tə koid′).USA pronunciation