cork: [14] The earliest ascertainable ancestor of cork is Spanish alcorque ‘cork sole’, which passed into English via Dutch kork. The initial al-, of course, suggests that this was of Arabic origin (al being the Arabic definite article), and it seems likely that it represents Arabic al-qūrq, which some have suggested came from Latin cortex ‘bark’, source of English cortex [17]. The use of cork for a bottle-stopper made from cork dates from the early 16th century. => cortex
