costless

from WordNet (r) 3.0 (2006)

costless
    adj 1: costing nothing; "complimentary tickets"; "free
           admission" [syn: {complimentary}, {costless}, {free},
           {gratis(p)}, {gratuitous}]

from The Collaborative International Dictionary of English v.0.48

Costless \Cost"less\ (k?st"l?s; 115), a.
   Costing nothing.
   [1913 Webster]

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