From WordNet (r) 2.0 (August 2003) [wn]:
sentinel
n : a person employed to watch for something to happen [syn:
lookout, lookout man, sentry, watch, spotter,
scout, picket]
From The Collaborative International Dictionary of English v.0.48 [gcide]:
Sentinel \Sen"ti*nel\, v. t. [imp. & p. p. Sentineledor
Sentinelled; p. pr. & vb. n. Sentineling or
Sentinelling.]
1. To watch over like a sentinel. "To sentinel enchanted
land." [R.] --Sir W. Scott.
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2. To furnish with a sentinel; to place under the guard of a
sentinel or sentinels.
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From The Collaborative International Dictionary of English v.0.48 [gcide]:
Sentinel \Sen"ti*nel\, n. [F. sentinelle (cf. It. sentinella);
probably originally, a litle path, the sentinel's beat,, and
a dim. of a word meaning, path; cf. F. sente path. L. semita;
and OF. sentine, sentele, senteret, diminutive words. Cf.
Sentry.]
1. One who watches or guards; specifically (Mil.), a soldier
set to guard an army, camp, or other place, from surprise,
to observe the approach of danger, and give notice of it;
a sentry.
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The sentinels who paced the ramparts. --Macaulay.
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2. Watch; guard. [Obs.] "That princes do keep due sentinel."
--Bacon.
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3. (Zool.) A marine crab (Podophthalmus vigil) native of
the Indian Ocean, remarkable for the great length of its
eyestalks; -- called also sentinel crab.
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