The Collaborative International Dictionary of English v.0.48:

Dissemblance \Dis*sem"blance\, n. [Cf. F. dissemblance. See
   Dissemble.]
   Want of resemblance; dissimilitude. [R.] --Osborne.
   [1913 Webster]

The Collaborative International Dictionary of English v.0.48:

Dissemblance \Dis*sem"blance\, n. [Dissemble + -ance.]
   The act or art of dissembling; dissimulation. [Obs.]
   [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

81 Moby Thesaurus words for "dissemblance":
   acting, affectation, appearance, attitudinizing, bad copy,
   bad likeness, bluff, bluffing, camouflage, cheating, color,
   coloring, contrast, cunning, deception, delusion, difference,
   discrepancy, disguise, disparity, dissembling, dissimilarity,
   dissimilation, dissimilitude, dissimulation, distinction,
   divergence, divergency, diversity, duplicity, facade, face, fakery,
   faking, false air, false front, false show, falsity, feigning,
   feint, four-flushing, fraud, front, gilt, gloss, guile, humbug,
   humbuggery, imposture, incommensurability, incomparability, makeup,
   masquerade, mere caricature, meretriciousness, nonuniformity,
   ostentation, otherness, outward show, playacting, poor imitation,
   pose, posing, posture, pretense, pretension, pretext,
   representation, seeming, semblance, sham, show, simulacrum,
   simulation, speciousness, unlikeness, unresemblance, unsameness,
   unsimilarity, varnish, window dressing