The Collaborative International Dictionary of English v.0.48:

Lowboy \Low"boy`\, n.
   A chest of drawers not more than four feet high; -- applied
   commonly to the lower half of a tallboy from which the upper
   half has been removed. [U. S.]
   [Webster 1913 Suppl.]

WordNet (r) 3.0 (2006):

lowboy
    n 1: a low chest or table with drawers and supported on four
         legs