The Collaborative International Dictionary of English v.0.48:

Ambulate \Am"bu*late\, v. i. [L. ambulare to walk. See Amble.]
   To walk; to move about. [R.] --Southey.
   [1913 Webster]

WordNet (r) 3.0 (2006):

ambulate
    v 1: walk about; not be bedridden or incapable of walking