pivot
n
1 a short shaft or pin supporting something that turns; fulcrum
2 the end of a shaft or arbor that terminates in a bearing
3 a person or thing upon which progress, success, etc., depends
4 the person or position from which a military formation takes its reference, as when altering position
vb
5 tr to mount on or provide with a pivot or pivots
6 intr to turn on or as if on a pivot (C17: from Old French; perhaps related to Old Provençal pua tooth of a comb)
pivot bridge
n another name for →
swing bridge
pivot grammar
n (Psychol) a loose grammar said to govern two-word utterances by children