Merriam-Webster's Collegiate® Dictionary, 11th Edition
PEAT
I. noun
Usage: often attributive
Etymology: Middle English pete piece of peat, from Medieval Latin peta, probably of Celtic origin; akin to Cornish peyth bit, Welsh peth thing
Date: 14th century
turf 2b, partially carbonized vegetable tissue formed by partial decomposition in water of various plants (as mosses of the genus Sphagnum ), peaty adjective
II. noun
Etymology: origin unknown
Date: 1599
a bold lively woman