1. A person employed to keep watch for some anticipated event Noun
2. A detachment of troops guarding an army from surprise attack Noun
3. A protester posted by a labor organization outside a place of work Noun
4. A vehicle performing sentinel duty Noun
5. A wooden strip forming part of a fence Noun
6. A form of military punishment used by the British in the late 17th century in which a soldier was forced to stand on one foot on a pointed stake Noun