I. ˈsent( ə )nəl, -tənəl noun
( -s )
Etymology: Middle French sentinelle, from Old Italian sentinella, from sentina vigilance, from sentire to perceive, from Latin — more at sense
1. : one that watches or guards : sentry
2.
a. obsolete : watch , guard
keep sentinel
b. obsolete : watchtower
c. : soldier
3. : an officer of a secret society who is stationed outside the door of a meeting place to prevent unauthorized entry — compare warder
II. transitive verb
( sentineled or sentinelled ; sentineled or sentinelled ; sentineling or sentinelling ; sentinels )
1. : to watch over as a sentinel
long lines of shivering poplars that sentinelled the meadows — Willa Cather
2. : to furnish with a sentinel : place under the guard of a sentinel or sentinels
3. : to post as sentinel