Other forms: sentinels
A sentinel is a guard posted to keep watch. Stand sentinel, a lone sentinel, sentinel duty.
It is more literary than sentry, which is the ordinary military word for the same job. In medicine, a sentinel event is a serious incident that must be investigated, and a sentinel node is the first lymph node a cancer would reach. In computing, a sentinel value marks the end of data. Note that the Italian behind it comes from a verb meaning to perceive.
1nounsentinelA guard posted to keep watch.
“A lone sentinel stood on the city wall, watching the road for enemies.”
2nounmarkerA marker or a warning case.
“The hospital treats any unexpected death on a ward as a sentinel event that must be investigated.”
sentinel is a watcher or marker.
French sentinelle comes from Italian sentinella, probably from sentire, to perceive. Sentiment, sense and assent come from the same perceiving.
roa-oit
sentinella
Middle French
sentinelle — watch or guard kept by a soldier
English, today
sentinel
Built from
1570s from Middle French sentinelle (“watch or guard kept by a soldier”), from roa-oit sentinella, probably from sentina + -ella, from sentire (“perceive, watch, hear”), from sentiō (“feel, perceive by the senses”). See also sense, sentient.
Etymology from Wiktionary, CC BY-SA