Real Dictionary

elbow
countable noun: Your elbow is the part of your arm where the upper and lower halves of the arm are joined.
verb: If someone or something elbows their way somewhere, or elbows other people or things out of the way, they achieve success by being aggressive and determined.
verb: If you elbow people aside or elbow your way somewhere, you push people with your elbows in order to move somewhere.

elbow in American English
the joint between the upper and lower arm; esp., the outer part of the angle made by a bent arm
to make one's way by shoving or jostling
to shove or jostle with or as with elbows
noun: the bend or joint of the human arm between upper arm and forearm

elbow in British English
noun: the joint between the upper arm and the forearm, formed by the junction of the radius and ulna with the humerus