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...
![Neural Control Mechanisms](https://www.biologyonline.com/wp-content/uploads/2020/02/Neural-Control-Mechanisms-300x152.jpg)
Neural Control Mechanisms
Neurons generate electric signals that they pass along to the other neurons or target tissues. In this tutorial, you wil..
![Population Growth and Survivorship](https://www.biologyonline.com/wp-content/uploads/2020/09/Population-Growth-and-Survivorship-300x168.jpg)
Population Growth and Survivorship
This lesson looks at population attributes, regulation, and growth. It also covers population genetics, particularly gen..
![Biological Viruses](https://www.biologyonline.com/wp-content/uploads/2020/02/Biological-Viruses-224x168.jpg)
Biological Viruses
Viruses possess both living and non-living characteristics. This unique feature distinguishes them from other organisms...
![](https://www.biologyonline.com/wp-content/uploads/2020/09/Community-Patterns-300x168.jpg)
Community Patterns
Learn about community patterns and the ecological factors influencing these patterns. Revisit some of the ecosystems you..
![Homeostatic Mechanisms and Cellular Communication](https://www.biologyonline.com/wp-content/uploads/2020/02/Homeostatic-Mechanisms-and-Cellular-Communication-259x168.jpg)
Homeostatic Mechanisms and Cellular Communication
Homeostasis is the relatively stable conditions of the internal environment that result from compensatory regulatory res..
![kinesin motor proteins transporting molecules across microtubules](https://www.biologyonline.com/wp-content/uploads/2020/02/Movement-of-molecules-across-cell-membranes-252x168.jpg)
Movement of Molecules Across Cell Membranes
Molecules move within the cell or from one cell to another through different strategies. Transport may be in the form of..