"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).
group of islands off the north coast of Scotland, from Old Norse Orkney-jar "Seal Islands," from orkn "seal," which is probably imitative of its bark. With Old Norse ey "island" (compare Jersey). Related: Orcadian; Orkneyman.
1806, from French croûton "small piece of toasted bread," used in soups, salads, etc., from croûte "crust," from Old French crouste (13c.), from Latin crusta "rind, crust, shell, bark" (from PIE root *kreus- "to begin to freeze, form a crust").
If this is correct, the sense development would be from "loft, ceiling" to "sky, air." Buck suggests a further connection with Old High German louft "bark," louba "roof, attic," etc., with development from "bark" to "roof made of bark" to "ceiling," though this did not directly inform the meaning "air, sky" (compare lodge (n.)). But Watkins says this is "probably a separate Germanic root." Meaning "gallery in a church" first attested c. 1500. From 1520s as "apartment over a stable" used for hay storage, etc.
c. 1300, "the light, elastic outer bark of a species of oak tree native to Iberia and North Africa, used for many purposes," from Spanish alcorque "cork sole," probably from earlier Spanish corcho, from Latin quercus "oak" (see Quercus) or cortex (genitive corticis) "bark" (see corium).
In reference to the tree itself, mid-15c. From late 14c. as "cork-soled shoe." As "cork float for a fishing line," mid-15c. Meaning "cylindrical cork stopper or bung for a bottle, etc.," 1520s. As an adjective, "made of cork," 1716.