headspring

from WordNet (r) 3.0 (2006)

headspring
    n 1: the source of water from which a stream arises; "they
         tracked him back toward the head of the stream" [syn:
         {fountainhead}, {headspring}, {head}]

from The Collaborative International Dictionary of English v.0.48

Headspring \Head"spring`\ (h[e^]d"spr[i^]ng`), n.
   Fountain; source.
   [1913 Webster]

         The headspring of our belief.            --Stapleton.
   [1913 Webster]

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