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

fifteen \fif"teen`\, a. oe. fiftene, as. fimacft=yne,
   fimacft=ene. see five, and ten, and cf. fifty.
   five and ten; one more than fourteen.
   1913 webster
see also:
five ten fifty 

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

fifteen \fif"teen`\, n.
   1. the sum of five and ten; fifteen units or objects.
      1913 webster

   2. a symbol representing fifteen units, as 15, or xv.
      1913 webster

[3] : WordNet (r) 2.0

fifteen
     adj : being one more than fourteen syn: 15, xv
     n : the cardinal number that is the sum of fourteen and one
         syn: 15, xv
see also:
15 xv xv 

Fifteen >> F Words
Fifteen, definition of term: Fifteen
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