sentinel
1. One who watches or guards; specifically, 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. The sentinels who paced the ramparts. (Macaulay)
2. Watch; guard. That princes do keep due sentinel.
3. (Science: zoology) A marine crab (Podophthalmus vigil) native of the indian ocean, remarkable for the great length of its eyestalks.
Synonym: sentinel crab.
Origin: 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.
Dictionary > Sentinel
You will also like...
Dominance
This tutorial presents Gregor Mendel's law of dominance. Learn more about this form of inheritance and how it can be pre..
Homeostasis of Organism Water Regulation
Osmoregulation is the regulation of water concentrations in the bloodstream, effectively controlling the amount of water..
Plant Meristems and Growth
In plants, growth occurs in meristems, which are the site of repeated cell division of unspecialized cells. These cells ..
Running Water Freshwater Communities
This tutorial introduces flowing water communities, which bring new and dithering factors into the equation for possible..
Circulation
The circulatory system is key to the transport of vital biomolecules and nutrients throughout the body. Learn about the ..
Respiration
The human respiratory system is an efficient system of inspiring and expiring respiratory gases. This tutorial provides ..