The Collaborative International Dictionary of English v.0.48:

Inky \Ink"y\, a.
   Consisting of, or resembling, ink; soiled with ink; black.
   "Inky blots." --Shak. "Its inky blackness." --Boyle.
   [1913 Webster]

WordNet (r) 3.0 (2006):

inky
    adj 1: of the color of black ink [syn: ink-black, inky,
           inky-black]

Moby Thesaurus II by Grady Ward, 1.0:

50 Moby Thesaurus words for "inky":
   atramentous, besmirched, black, black as coal, black as ebony,
   black as ink, black as midnight, black as night, blackened,
   coal-black, coaly, dark, dark as night, dark as pitch, darkened,
   deep black, discolored, ebon, ebony, flack, foxed, foxy, ink-black,
   jet, jetty, midnight, murky, night-black, night-dark, nigrous,
   pitch-black, pitch-dark, pitchy, raven, raven-black, sable, sloe,
   sloe-black, sloe-colored, smirched, smoky, soiled, stained,
   stigmatic, stigmatiferous, stigmatized, tainted, tar-black,
   tarnished, tarry