universal joint

American Heritage® Dictionary of the English Language, Fourth Edition

1. n. A joint or coupling that allows parts of a machine not in line with each other limited freedom of movement in any direction while transmitting rotary motion. Also called universal coupling.

Wiktionary

1. n. A coupling that allows different parts of a machine not in line with each other some freedom of movement at the same time as transmitting rotary motion.

GNU Webster's 1913

1. adj. (Mach.) a contrivance used for joining two shafts or parts of a machine endwise, so that the one may give rotary motion to the other when forming an angle with it, or may move freely in all directions with respect to the other, as by means of a cross connecting the forked ends of the two shafts (Fig. 1). Since this joint can not act when the angle of the shafts is less than 140°, a double joint of the same kind is sometimes used for giving rotary motion at angles less than 140° (Fig. 2).

WordNet 3.0

1. n. coupling that connects two rotating shafts allowing freedom of movement in all directions