Definitions
1.nounA seat across a boat on which a rower may sit."The fisherman sat on the aft thwart to row."
2.nounA brace, perpendicular to the keel, that helps maintain the beam of a marine vessel against external water pressure and that may serve to support the rail."A well-made dugout canoe rarely needs a thwart."
3.nounAn act of thwarting; something which thwarts; a hindrance, an obstacle.
4.verbTo cause to fail; to frustrate, to prevent."Our plans for a picnic were thwarted by the thunderstorm."
5.verbTo place (something) across (another thing); to position crosswise.
6.verbTo hinder or obstruct by placing (something) in the way of; to block, to impede, to oppose.
7.verbTo move (something) across or counter to; to cross."An arrow thwarts the air."