The Collaborative International Dictionary of English v.0.48:

Lanky \Lank"y\, a.
   Somewhat lank; tall, thin, bony and ungraceful. --Thackeray.
   [1913 Webster]

         The lanky Dinka, nearly seven feet in height. --The
                                                  Century.
   [1913 Webster] Lanner

WordNet (r) 3.0 (2006):

lanky
    adj 1: tall and thin and having long slender limbs; "a gangling
           teenager"; "a lanky kid transformed almost overnight into
           a handsome young man" [syn: gangling, gangly,
           lanky, rangy]
    2: tall and thin [syn: gangling, gangly, lanky]

Moby Thesaurus II by Grady Ward, 1.0:

39 Moby Thesaurus words for "lanky":
   angular, bony, colossal, flat, flat-chested, fleshless, gangling,
   gangly, gaunt, gawky, giant, gigantic, lank, lean, lean-fleshed,
   lean-looking, leggy, lengthy, long, long-legged, meager, rangy,
   rawboned, scraggy, scrawny, skeletal, skinny, spare, spidery,
   spindling, spindly, statuesque, tall, thin, thin-bellied,
   thin-fleshed, twiggy, undersized, underweight