[1] : The Collaborative International Dictionary of English v.0.48

sweetheart \sweet"heart`\, n.
   a lover of mistress.
   1913 webster

[2] : WordNet (r) 2.0

sweetheart
     adj : privileged treatment of a favored person or corporation
           sometimes unethically; "another sweetheart deal based
           on political influence"
     n 1: a person loved by another person syn: sweetie, steady,
          truelove
     2: any well-liked individual; "he's a sweetheart"
     3: a very attractive or seductive looking woman syn: smasher,
         stunner, knockout, beauty, ravisher, peach, lulu,
         looker, mantrap, dish
see also:
sweetie steady truelove smasher stunner knockout 
beauty ravisher peach lulu looker 
mantrap dish 

[3] : Moby Thesaurus II by Grady Ward, 1.0

84 moby thesaurus words for "sweetheart":
   ace, admirer, angel, babe, baby, baby-doll, beau, beaut, beloved,
   betrothed, boyfriend, buttercup, captive, catch, cherub, chick,
   chickabiddy, conquest, coquette, corker, court, crackerjack, daisy,
   dandy, darb, darling, date, dear, deary, dilly, doll, dream,
   dreamboat, duck, duckling, fiancee, flame, flirt, friend,
   heartthrob, hon, honey, honey bunch, honey child, humdinger,
   inamorata, inamorato, intended, killer-diller, knockout, ladylove,
   lamb, lambkin, lollapaloosa, love, lover, lulu, make up to,
   paramour, peach, pet, petkins, pip, pippin, precious,
   precious heart, pursue, snookums, spark, steady, sue, sugar, sweet,
   sweet patootie, sweetie, sweetkins, sweets, the nuts, truelove,
   turtledove, vamp, vampire, whiz, woo

Sweetheart >> S Words
Sweetheart, definition of term: Sweetheart
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