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

three \three\, n.
   1. the number greater by a unit than two; three units or
      objects.
      1913 webster

   2. a symbol representing three units, as 3 or iii.
      1913 webster

   rule of three. arith. see under rule, n.
      1913 webster
see also:
rule of three rule 

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

three \three\ thr=e, a. oe. thornre, thornreo,
   thornri, as. thornrimac, masc., thornre'o, fem. and
   neut.; akin to ofries. thre, os. thria, threa, d. drie, g.
   drei, ohg. drimac, icel. thornrimacr, dan.  sw. tre,
   goth. thornreis, lith. trys, ir., gael.  w. tri, russ.
   tri, l. tres, gr. trei^s, skr. tri. root301. cf. 3d
   drilling, tern, a., third, thirteen, thirty,
   tierce, trey, tri-, triad, trinity, tripod.
   one more than two; two and one. "i offer thee three things."
   --2 sam. xxiv. 12.
   1913 webster

         three solemn aisles approach the shrine. --keble.
   1913 webster

   note: three is often joined with other words, forming
         compounds signifying divided into, composed of, or
         containing, three parts, portions, organs, or the like;
         as, three-branched, three-capsuled, three-celled,
         three-cleft, three-edged, three-foot, three-footed,
         three-forked, three-grained, three-headed,
         three-legged, three-mouthed, three-nooked,
         three-petaled, three-pronged, three-ribbed,
         three-seeded, three-stringed, three-toed, and the like.
         1913 webster
see also:
drilling tern third thirteen thirty tierce 
trey tri- triad trinity tripod 

[3] : WordNet (r) 2.0

three
     adj : being one more than two syn: 3, iii
     n : the cardinal number that is the sum of one and one and one
         syn: 3, iii, trio, threesome, tierce, leash,
          troika, triad, trine, trinity, ternary, ternion,
          triplet, tercet, terzetto, trey, deuce-ace
see also:
3 iii iii trio threesome tierce 
leash troika triad trine trinity 
ternary ternion triplet tercet terzetto 
trey deuce-ace 

Three >> T Words
Three, definition of term: Three
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Three Piece Sui >> T Words
Three Piece Sui, definition of term: Three Piece Sui
three+piece+sui_pag1.html