The Collaborative International Dictionary of English v.0.48:

Curt \Curt\ (k[u^]rt), a. [L. curtus; cf. Skr. kart to cut. Cf.
   Curtail.]
   Characterized by excessive brevity; short; rudely concise;
   as, curt limits; a curt answer.
   [1913 Webster]

         The curt, yet comprehensive reply.       --W. Irving.
   [1913 Webster]

WordNet (r) 3.0 (2006):

curt
    adj 1: marked by rude or peremptory shortness; "try to cultivate
           a less brusque manner"; "a curt reply"; "the salesgirl
           was very short with him" [syn: brusque, brusk,
           curt, short(p)]
    2: brief and to the point; effectively cut short; "a crisp
       retort"; "a response so curt as to be almost rude"; "the
       laconic reply; `yes'"; "short and terse and easy to
       understand" [syn: crisp, curt, laconic, terse]

Moby Thesaurus II by Grady Ward, 1.0:

87 Moby Thesaurus words for "curt":
   Spartan, abbreviated, abridged, abrupt, aggressive, aposiopestic,
   bearish, beastly, bluff, blunt, brash, brief, brusque, cavalier,
   churlish, clipped, close, close-tongued, closemouthed, compact,
   compendious, compressed, concise, condensed, contracted, crisp,
   crusty, curtal, curtate, cut, decurtate, docked, dumb,
   economical of words, elliptic, epigrammatic, gnomic, gruff, harsh,
   imperious, indisposed to talk, instantaneous, laconic, little, low,
   mum, mute, peremptory, pithy, pointed, pruned, quiet, reserved,
   rough, rude, sententious, severe, sharp, short, short and sweet,
   shortened, silent, snappish, snippety, snippy, snug,
   sparing of words, speechless, succinct, summary, surly, synopsized,
   synoptic, taciturn, terse, tight, tight-lipped, to the point,
   tongue-tied, transient, truculent, truncated, unceremonious,
   unloquacious, untalkative, word-bound, wordless