1. 
[syn: sphagnum, sphagnum moss, peat moss, bog moss]
The Collaborative International Dictionary of English v.0.48:
Sphagnum \Sphag"num\, n. [NL., fr/ Gr. ??? a kind of moss.]
   (Bot.)
   A genus of mosses having white leaves slightly tinged with
   red or green and found growing in marshy places; bog moss;
   peat moss.
   [1913 Webster]
WordNet (r) 3.0 (2006):
sphagnum
    n 1: any of various pale or ashy mosses of the genus Sphagnum
         whose decomposed remains form peat [syn: sphagnum,
         sphagnum moss, peat moss, bog moss]