Wordnet 3.0
NOUN (1)
1.
a marauder and plunderer (originally operating in the bogs between England and Scotland);
The Collaborative International Dictionary of English v.0.48:
Mosstrooper \Moss"troop`er\, n. [Moss + trooper.]
One of a class of marauders or bandits that formerly infested
the border country between England and Scotland; -- so called
in allusion to the mossy or boggy character of much of the
border country.
[1913 Webster]
WordNet (r) 3.0 (2006):
moss-trooper
n 1: a marauder and plunderer (originally operating in the bogs
between England and Scotland)