The Collaborative International Dictionary of English v.0.48:

Cranky \Crank"y\ (-?), a.
   1. Full of spirit; crank.
      [1913 Webster]

   2. Addicted to crotchets and whims; unreasonable in opinions;
      crotchety. [Colloq.]
      [1913 Webster]

   3. Unsteady; easy to upset; crank.
      [1913 Webster]

WordNet (r) 3.0 (2006):

cranky
    adj 1: (used of boats) inclined to heel over easily under sail
           [syn: crank, cranky, tender, tippy]
    2: easily irritated or annoyed; "an incorrigibly fractious young
       man"; "not the least nettlesome of his countrymen" [syn:
       cranky, fractious, irritable, nettlesome, peevish,
       peckish, pettish, petulant, scratchy, testy,
       tetchy, techy]

Moby Thesaurus II by Grady Ward, 1.0:

202 Moby Thesaurus words for "cranky":
   abnormal, anomalous, antagonistic, antipathetic, arbitrary,
   at cross-purposes, at loggerheads, at odds, at variance, at war,
   bearish, beefing, bellyaching, bitching, bitchy, breakaway,
   cankered, cantankerous, capricious, choleric, churlish, clashing,
   complaining, complaintful, conflicting, contentious, contradicting,
   contradictory, contrary, counteractant, counteracting,
   counteractive, countervailing, counterworking, crabbed, crabbing,
   crabby, crackbrained, cracked, crackers, crank, crankish, crazed,
   crazy, croaking, cross, cross-grained, crotchety, crusty, cuckoo,
   cussed, daffy, daft, deviant, deviative, different, differing,
   difficult, disaccordant, disagreeable, disagreeing, disappointed,
   discontented, discordant, discrepant, disgruntled, disharmonious,
   displeased, disproportionate, dissatisfied, dissident, dissonant,
   divergent, dotty, eccentric, envious, erratic, exceptional,
   excitable, fanciful, fantasied, fantastic, faultfinding, feisty,
   fey, flaky, fractious, freakish, froward, funny, grating, griping,
   grouchy, grousing, growling, gruff, grumbling, harebrained,
   hostile, hot-tempered, huffish, huffy, humorsome, idiocratic,
   idiosyncratic, ill-humored, immiscible, inaccordant, incompatible,
   inharmonious, inimical, irascible, irregular, irritable, jangling,
   jarring, kinky, kooky, maggoty, malcontent, malcontented, mean,
   moody, motiveless, murmuring, muttering, negative, nonconformist,
   notional, nutty, odd, oddball, opposing, oppositional, oppugnant,
   ornery, out of accord, out of humor, out of sorts, out of whack,
   peculiar, peevish, perverse, petulant, queer, querulant, querulous,
   quick-tempered, quirky, ratty, reactionary, rebellious,
   recalcitrant, renitent, repugnant, resentful, resistant, restive,
   restless, revolutionary, screwball, screwy, short-tempered,
   singular, snappish, spiteful, spleeny, splenetic, strange, sulky,
   surly, temperamental, testy, tetchy, touchy, twisted, ugly,
   unaccepting, unaccommodating, uncongenial, unconventional, uneasy,
   unfulfilled, ungratified, unhappy, unharmonious, unnatural,
   unreasonable, unrestrained, unsatisfied, vagarious, vagrant,
   variant, vinegarish, vinegary, wacky, wanton, waspish, wayward,
   weird, whimsical, whiny