The Collaborative International Dictionary of English v.0.48:

Snuffy \Snuff"y\, a.
   1. Soiled with snuff.
      [1913 Webster]

   2. Sulky; angry; vexed. [Obs. or Scot.] --Jamieson.
      [1913 Webster]

Moby Thesaurus II by Grady Ward, 1.0:

51 Moby Thesaurus words for "snuffy":
   asthmatic, breathing, chewing, dingy, dirty, dusty, errhine,
   expiratory, grimy, grubby, grungy, heaving, huffing, inspiratory,
   messy, miry, muddy, nasal, nicotinic, panting, pneumonic, puffing,
   pulmonary, pulmonic, respiratory, rhinal, scruffy, slovenly,
   smirchy, smoking, smoky, smudgy, smutchy, smutty, sneezy,
   sniffling, sniffly, sniffy, snoring, snorting, snuffling, snuffly,
   sooty, sternutatory, stertorous, tobacco, tobaccolike, tobaccoy,
   untidy, wheezing, wheezy