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 Gloucester)
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. 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.
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 labour. Elbow in the hawse, scissors bent in the blade or shank for convenience in cutting. Out at elbow, with coat worn through at the elbows; shabby; in needy circumstances.
Origin: 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.