WordNet (r) 3.0 (2006):

spruce up
    v 1: make neat, smart, or trim; "Spruce up your house for
         Spring"; "titivate the child" [syn: spruce up, spruce,
         titivate, tittivate, smarten up, slick up, spiff
         up]
    2: dress and groom with particular care, as for a special
       occasion; "He spruced up for the party" [syn: spruce up,
       spruce, slick up, smarten up]

Moby Thesaurus II by Grady Ward, 1.0:

83 Moby Thesaurus words for "spruce up":
   adorn, array, beautify, bedeck, bedizen, blazon, brighten up,
   brush up, clean up, clear the decks, clear up, color, dandify,
   deck, deck out, decorate, dizen, doll up, dress, dress up,
   embellish, emblazon, embroider, enrich, fancy up, fig out, fix,
   fix up, freshen, furbish, furbish up, garnish, get up, grace,
   groom, gussy up, neaten, ornament, overdress, paint, police,
   police up, polish, polish up, prank, prank up, preen, prettify,
   pretty up, primp, primp up, prink, prink up, put in trim, rag out,
   redecorate, redo, refurbish, renovate, repair, retouch, revive,
   rub up, set off, set out, shine, slick up, smarten, smarten up,
   spruce, straighten up, tidy, tidy up, titivate, tone up, touch up,
   trick out, trick up, trig up, trim, trim up, vamp, vamp up