WordNet (r) 3.0 (2006):

spidery
    adj 1: relating to or resembling a member of the class Arachnida
           [syn: arachnoid, arachnidian, spidery,
           spiderlike, spiderly]

Moby Thesaurus II by Grady Ward, 1.0:

42 Moby Thesaurus words for "spidery":
   bony, dilapidated, doddering, flat, flat-chested, fleshless,
   gangling, gangly, gaunt, gawky, groggy, lank, lanky, lean,
   lean-fleshed, lean-looking, meager, ramshackle, rawboned,
   ricketish, rickety, rocky, scraggy, scrawny, shaky, skeletal,
   skinny, spare, spindling, spindly, teetering, teetery,
   thin-bellied, thin-fleshed, tottering, tottery, tumbledown, twiggy,
   undersized, underweight, unsteady, wobbly