The Collaborative International Dictionary of English v.0.48:

Cubby \Cub"by\ (k?b"b?), Cubbyhole \Cub"by*hole`\ (-h?l`), n.
   [See Cub a stall.]
   A snug or confined or secluded place; a small room or a snug
   space within a room.

   Syn: snuggery, snug.
        [1913 Webster +PJC]

The Collaborative International Dictionary of English v.0.48:

cubbyhole \cubbyhole\ n.
   a small compartment.

   Syn: pigeonhole.
        [WordNet 1.5]

WordNet (r) 3.0 (2006):

cubbyhole
    n 1: a small compartment [syn: cubbyhole, pigeonhole]
    2: a small secluded room [syn: cubby, cubbyhole, snuggery,
       snug]

Moby Thesaurus II by Grady Ward, 1.0:

46 Moby Thesaurus words for "cubbyhole":
   alcove, asylum, bay, bolt-hole, cache, carrel, concealment, corner,
   cove, cover, covert, coverture, cranny, cubby, cubicle,
   dark corner, den, doghouse, dugout, foxhole, funk hole, hideaway,
   hideout, hidey hole, hiding, hiding place, hole, lair, mousehole,
   niche, nook, oriel, pigeonhole, pinch, playhouse, recess, refuge,
   retreat, roomlet, sanctuary, secret place, snuggery, stash,
   tight spot, tight squeeze, undercovert