The Collaborative International Dictionary of English v.0.48:
Elbow \El"bow\, n. [AS. elboga, elnboga (akin to D. elleboga,
OHG. elinbogo, G. ellbogen, ellenbogen, Icel. ?lnbogi; prop.;
arm-bend); eln ell (orig., forearm) + boga a bending. See 1st
Ell, and 4th Bow.]
1. The joint or bend of the arm; the outer curve in the
middle of the arm when bent.
Her arms to the elbows naked. --R. of
2. Any turn or bend like that of the elbow, in a wall,
building, and the like; a sudden turn in a line of coast
or course of a river; also, an angular or jointed part of
any structure, as the raised arm of a chair or sofa, or a
short pipe fitting, turning at an angle or bent.
3. (Arch.) A sharp angle in any surface of wainscoting or
other woodwork; the upright sides which flank any paneled
work, as the sides of windows, where the jamb makes an
elbow with the window back. --Gwilt.
Note: Elbow is used adjectively or as part of a compound, to
denote something shaped like, or acting like, an elbow;
as, elbow joint; elbow tongs or elbow-tongs; elbowroom,
elbow-room, or elbow room.
At the elbow, very near; at hand.
Elbow grease, energetic application of force in manual
Elbow in the hawse (Naut.), the twisting together of two
cables by which a vessel rides at anchor, caused by
swinging completely round once. --Totten.
Elbow scissors (Surg.), scissors bent in the blade or shank
for convenience in cutting. --Knight.
Out at elbow, with coat worn through at the elbows; shabby;
in needy circumstances.