The Collaborative International Dictionary of English v.0.48:

dinky \dinky\ adj.
   1. small and insignificant; shabby or unimpressive; as, he
      drove to work in a dinky old Volkswagen; we stayed in a
      dinky little hotel. [informal]
      [WordNet 1.5]

   2. pretty and neat; fashionable or well-dressed; as, what a
      dinky little hat. [British informal]
      [WordNet 1.5]

WordNet (r) 3.0 (2006):

dinky
    adj 1: small and insignificant; "we stayed in a dinky old hotel"
    2: (British informal) pretty and neat; "what a dinky little hat"
    n 1: a small locomotive [syn: dinky, dinkey]

Moby Thesaurus II by Grady Ward, 1.0:

56 Moby Thesaurus words for "dinky":
   anal, back-burner, cramped, dispensable, exiguous, half-pint,
   immaterial, inappreciable, inconsequential, inconsiderable,
   inessential, inferior, insignificant, irrelevant, knee-high,
   lesser, limited, little, minor, minute, neat, negligible,
   nonessential, not vital, one-horse, petit, petite, piddling,
   pindling, pint-sized, poky, puny, secondary, shipshape, short,
   sleek, slick, slight, small, small-fry, small-time, smallish,
   smart, snug, spruce, technical, tidy, tight, trig, trim,
   two-by-four, unessential, unimpressive, unnoteworthy,
   well-cared-for, well-groomed