The Collaborative International Dictionary of English v.0.48:

Scaly \Scal"y\, a.
   1. Covered or abounding with scales; as, a scaly fish. "Scaly
      crocodile." --Milton.
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   2. Resembling scales, laminae, or layers.
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   3. Mean; low; as, a scaly fellow. [Low]
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   4. (Bot.) Composed of scales lying over each other; as, a
      scaly bulb; covered with scales; as, a scaly stem.
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   Scaly ant-eater (Zool.), the pangolin.
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WordNet (r) 3.0 (2006):

scaly
    adj 1: rough to the touch; covered with scales or scurf [syn:
           lepidote, leprose, scabrous, scaly, scurfy]
    2: having the body covered or partially covered with thin horny
       plates, as some fish and reptiles [syn: scaly, scaley,
       scaled]

Moby Thesaurus II by Grady Ward, 1.0:

51 Moby Thesaurus words for "scaly":
   asperous, branny, chalklike, chalky, comminute, comminuted,
   crushed, detrital, detrited, disintegrated, dusty, efflorescent,
   farinaceous, fine, flaky, flocculent, floury, furfuraceous,
   gone to dust, grated, ground, imbricated, impalpable, lamellar,
   lamellate, laminar, lentiginous, lepidote, levigated, mealy,
   milled, pestled, powdered, powdery, pulverant, pulverized,
   pulverulent, reduced to powder, rough, scabby, scabious, scabrous,
   scobicular, scobiform, scruffy, scurfy, sharded, shingly, shredded,
   squamous, triturated