From The Collaborative International Dictionary of English v.0.48:
Sag \Sag\ (s[a^]g), v. i. [imp. & p. p. Sagged; p. pr. & vb.
n. Sagging.] [Akin to Sw. sacka to settle, sink down, LG.
sacken, D. zakken. Cf. Sink, v. i.]
1. To sink, in the middle, by its weight or under applied
pressure, below a horizontal line or plane; as, a line or
cable supported by its ends sags, though tightly drawn;
the floor of a room sags; hence, to lean, give way, or
settle from a vertical position; as, a building may sag
one way or another; a door sags on its hinges.
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2. Fig.: To lose firmness or elasticity; to sink; to droop;
to flag; to bend; to yield, as the mind or spirits, under
the pressure of care, trouble, doubt, or the like; to be
unsettled or unbalanced. [R.]
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The mind I sway by, and the heart I bear,
Shall never sag with doubt nor shake with fear.
--Shak.
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3. To loiter in walking; to idle along; to drag or droop
heavily.
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To sag to leeward (Naut.), to make much leeway by reason of
the wind, sea, or current; to drift to leeward; -- said of
a vessel. --Totten.
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From The Collaborative International Dictionary of English v.0.48:
Sagging \Sag"ging\, n.
A bending or sinking between the ends of a thing, in
consequence of its own, or an imposed, weight; an arching
downward in the middle, as of a ship after straining. Cf.
Hogging.
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