In full "Mount (of) Olivet". The Mount of Olives on the east side of Jerusalem, the scene of Christ's Ascension.
In Old English also in full dūn Olifetes, mōr Olifetes.
Old English. From classical Latin olīvētum olive grove from olīva + -ētum.
1An oval button or piece of wood covered with silk or worsted and used for fastening a garment by means of a loop of braid.
In form olivette. A small oval weight, threaded on to a fishing line.
Early 19th century; earliest use found in Army List. Apparently from French olivette fake pearl from olive + -ette. French olivette is apparently not attested in sense 1; however, compare olive olive-shaped button.