bob up Definition

bob¹
verb bobbed, bobbing

intr
1. To move up and down quickly.

Example: a stick bobbing along on the water
Thesaurus: duck, weave, wobble, jerk, jolt, quiver, falter, swing, oscillate.
Form: bob along (sometimes)
Form: bob past
2. To move (the head) up and down, usually as a greeting.
intr
3. To try to catch (especially an apple floating on water or suspended on a string) with one's teeth, as a game.

Form: bob for something (usually)
intr
4. To make a quick curtsy.

noun

1. A quick up-and-down bouncing movement.
2. A quick curtsy.

Etymology: 14c.

Phrasal Verb: bob up

To appear or reappear suddenly.