WordNet (r) 3.0 (2006):

climb down
    v 1: come down; "the birds alighted" [syn: alight, climb
         down]

Moby Thesaurus II by Grady Ward, 1.0:

35 Moby Thesaurus words for "climb down":
   abjure, alight, back down, back out, backwater, crawfish out, deny,
   disavow, disclaim, dismount, disown, eat crow, eat dirt,
   eat humble pie, forswear, get down, get off, land, lick the dust,
   light, perch, recant, renege, renounce, repudiate, retract, revoke,
   settle, sing small, swallow, take back, touch down, unhorse, unsay,
   withdraw