The definition of a sentinel is a person or animal that keeps guard.(noun)
An example of a sentinel is a security worker.
To sentinel is defined as to watch over or to provide with a guard.(verb)
An example of sentinel is to keep watch over a museum at night.
See sentinel in Webster's New World College Dictionary
Origin: Fr sentinelle < It sentinella, ult. < L sentire, to feel, sense
See sentinel in American Heritage Dictionary 4
Origin: French sentinelle
Origin: , from Italian sentinella
Origin: , probably from Old Italian sentina, vigilance
Origin: , from sentire, to watch
Origin: , from Latin sentīre, to feel; see sent- in Indo-European roots.
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