Merriam-Webster Collegiate Dictionary - stagger

 I. verb  (~ed; ~ing)  Etymology: alteration of earlier stacker, from Middle English stakeren, from Old Norse stakra, frequentative of staka to push; perhaps akin to Old English staca stake — more at stake  Date: 15th century  intransitive verb  1.  a. to reel from side to side ; totter  b. to move on unsteadily ~ed toward the door  2. to waver in purpose or action ; hesitate  3. to rock violently the ship ~ed  transitive verb  1. to cause to doubt or hesitate ; perplex  2. to cause to reel or totter  3. to arrange in any of various zigzags, alternations, or overlappings of position or time ~ work shifts ~ teeth on a cutter  • ~er noun  II. noun  Date: 1577  1. plural but singular or plural in construction an abnormal condition of domestic animals associated with damage to the central nervous system and marked by incoordination and a reeling unsteady gait  2. a reeling or unsteady gait or stance  3. an arrangement in which the leading edge of the upper wing of a biplane is advanced over that of the lower  III. adjective  Date: 1918 marked by an alternating or overlapping pattern