From WordNet (r) 3.0 (2006):
Plough
n 1: a group of seven bright stars in the constellation Ursa
Major [syn: Big Dipper, Dipper, Plough, Charles's
Wain, Wain, Wagon]
2: a farm tool having one or more heavy blades to break the soil
and cut a furrow prior to sowing [syn: plow, plough]
v 1: move in a way resembling that of a plow cutting into or
going through the soil; "The ship plowed through the water"
[syn: plow, plough]
2: to break and turn over earth especially with a plow; "Farmer
Jones plowed his east field last week"; "turn the earth in
the Spring" [syn: plow, plough, turn]