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

sappy \sap"py\, a. written also sapy. cf. l. sapere to
   taste.
   musty; tainted. obs.
   1913 webster
see also:
sapy 

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

sappy \sap"py\, a. compar. sappier; superl. sappiest.
   from 1st sap.
   1913 webster
   1. abounding with sap; full of sap; juicy; succulent.
      1913 webster

   2. hence, young, not firm; weak, feeble.
      1913 webster

            when he had passed this weak and sappy age.
                                                  --hayward.
      1913 webster

   3. weak in intellect. low
      1913 webster

   4. bot. abounding in sap; resembling, or consisting largely
      of, sapwood.
      1913 webster
see also:
sappier sappiest sap 

[3] : WordNet (r) 2.0

sappy
     adj 1: pungent adjectives of disesteem; "gave me a cockamamie
            reason for not going"; "wore a goofy hat"; "a silly
            idea"; "some wacky plan for selling more books" syn:
            cockamamie, cockamamy, goofy, silly, wacky,
            whacky, zany, unreasonable
     2: abounding in sap; "sappy maple trees"; "sappy kindling wood"
     also: sappiest, sappier
see also:
cockamamie cockamamy goofy silly wacky whacky 
zany unreasonable sappiest sappier 

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

121 moby thesaurus words for "sappy":
   absurd, apish, asinine, balmy, bathetic, batty, beery, befooled,
   beguiled, besotted, brainless, budding, buffoonish, callow,
   cloying, cockeyed, crazy, credulous, daffy, daft, dazed, dewy,
   dizzy, doting, drippy, dumb, fantastic, fatuitous, fatuous, flaky,
   flowing, fluent, fluid, fluidal, fluidic, fluxible, fluxile,
   fluxional, fluxionary, fond, fool, foolheaded, foolish, fuddled,
   futile, gaga, gooey, goofy, green, growing, gulled, gushing,
   harebrained, idiotic, imbecile, immature, impubic, inane, inept,
   inexperienced, infatuated, ingenuous, innocent, insane, intact,
   juicy, kooky, liquid, liquidy, loony, mad, maudlin, mawkish, minor,
   moronic, mushy, naive, namby-pamby, new-fledged, nostalgic,
   nostomanic, nutty, oversentimental, oversentimentalized,
   preposterous, raw, ripening, romantic, runny, screwy, senseless,
   sentimental, sentimentalized, silly, sloppy, slushy, soft, soppy,
   soupy, sticky, stupid, succulent, tear-jerking, teary, tender,
   thoughtless, unadult, underage, undeveloped, unfledged, unformed,
   unlicked, unmellowed, unripe, unseasoned, vernal, virginal, wacky,
   watery, wet, witless

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