Толковый словарь английского языка Oxford English Reference - sag

v. & n. --v.intr. (sagged, sagging) 1 sink or subside under weight or pressure, esp. unevenly. 2 have a downward bulge or curve in the middle. 3 fall in price. 4 (of a ship) drift from its course, esp. to leeward. --n. 1 a the amount that a rope etc. sags. b the distance from the middle of its curve to a straight line between its supports. 2 a sinking condition; subsidence. 3 a fall in price. 4 Naut. a tendency to leeward. Derivatives saggy adj. Etymology: ME f. MLG sacken, Du. zakken subside