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

gaga \gaga\ adj.
   1. mentally or physically infirm with age.

   syn: doddering, senile.
        wordnet 1.5

   2. marked by foolish or unreasoning fondness; as, gaga over
      his girlfriend.

   syn: crazy about, dotty, enamored, infatuated, in love,
        smitten, soft onpredicate, taken withpredicate.
        wordnet 1.5

[2] : WordNet (r) 2.0

gaga
     adj 1: mentally or physically infirm with age; "his mother was
            doddering and frail" syn: doddering, doddery, senile
     2: marked by foolish or unreasoning fondness; "she was crazy
        about him"; "gaga over the rock group's new album"; "he
        was infatuated with her" syn: crazy, dotty, enamored,
         infatuated, in love, smitten, soft onp, taken
        withp
see also:
doddering doddery senile crazy dotty enamored 
infatuated in love smitten soft onp taken withp 

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

113 moby thesaurus words for "gaga":
   ape about, apish, asinine, balmy, bananas, barmy, bats, batty,
   beany, befooled, beguiled, besotted, bonkers, brainless,
   buffoonish, buggy, bughouse, bugs, bugs on, cockeyed, cracked on,
   crackers, crazy, crazy about, credulous, cuckoo, daffy, daft,
   dazed, dippy, dizzy, doting, dotty, dumb, empty-headed, fatuitous,
   fatuous, featherbrained, featherheaded, flaky, flipped, fluttery,
   fond, fool, foolheaded, foolish, freaked-out, frivolous,
   fruitcakey, fruity, fuddled, futile, gaga over, giddy,
   giddy-brained, giddy-headed, giddy-pated, giddy-witted, gone on,
   goofy, gulled, harebrain, harebrained, haywire, hepped up over,
   hipped on, hot about, idiotic, imbecile, inane, inept, infatuated,
   insane, just plain nuts, kooky, loony, loopy, mad, mad about,
   maudlin, moronic, nuts, nuts about, nuts on, nutty, off the hinges,
   off the track, off the wall, potty, rattlebrained, rattleheaded,
   rattlepated, round the bend, sappy, scatterbrained,
   scramblebrained, screwball, screwballs, screwy, senseless,
   sentimental, shatterbrained, silly, slaphappy, starry-eyed over,
   steamed up about, stupid, thoughtless, turned-on, wacky, wet,
   wild about, witless

Gaga >> G Words
Gaga, definition of term: Gaga
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