from
The Collaborative International Dictionary of English v.0.48
Back \Back\, v. i.
1. To move or go backward; as, the horse refuses to back.
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2. (Naut.) To change from one quarter to another by a course
opposite to that of the sun; -- used of the wind.
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3. (Sporting) To stand still behind another dog which has
pointed; -- said of a dog. [Eng.]
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{To back and fill}, to manage the sails of a ship so that the
wind strikes them alternately in front and behind, in
order to keep the ship in the middle of a river or channel
while the current or tide carries the vessel against the
wind. Hence: (Fig.) To take opposite positions
alternately; to assert and deny. [Colloq.]
{To back out}, {To back down}, to retreat or withdraw from a
promise, engagement, or contest; to recede. [Colloq.]
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Cleon at first . . . was willing to go; but, finding
that he [Nicias] was in earnest, he tried to back
out. --Jowett
(Thucyd. )
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