STAGGER

noun

1. An unsteady movement of the body in walking or standing as if one were about to fall; a reeling motion
2. A disease of horses and other animals, attended by reeling, unsteady gait or sudden falling
3. Bewilderment; perplexity.

verb

1. Sway unsteadily, reel, or totter.
2. Doubt, waver, be shocked.
3. Have multiple groups doing the same thing in a uniform fashion, but starting at different, evenly-spaced, times or places (attested from 1856).