Old English eln, of Germanic origin; from an Indo-European root shared by Latin ulna (see ulna). Compare with elbow and also with cubit (the measure was originally linked to the length of the human arm or forearm).

• bow from Old English:

  The bow of a ship has nothing to do with a person bowing in respect or a support bowing under pressure. The nautical bow (early 17th century) is in fact related to bough (Old English), the limb of a tree. Its immediate source, in the later Middle Ages, was German or Dutch. The phrase a shot across the bows, ‘a warning statement or gesture’, has its origins in the world of naval warfare, where it is one which is not intended to hit, but to make ships stop or alter their course. See also buxom. The archer's bow and the act of bending, both Old English, are related and come from Germanic roots. The archer's bow got its name from the shape, which also appears in Old English rainbow and elbow (Old English). The first part of the latter gives us the old measurement the ell, a variable measure, originally the distance from elbow to fingertip, which comes from the Indo-European root that also gives us ulna (mid 16th century) for the bone that runs from elbow to wrist.