The term 'Like a Sentry' can be described by three crossword solutions: ALERT (5 letters), WARY (4 letters), and ONGUARD (7 letters). ALERT is an adjective meaning to be watchful and attentive, while WARY is an adjective meaning to be cautious and vigilant. ONGUARD is an adverb meaning to be on guard or to be prepared for danger. Together, these three words describe the behavior of a sentry, who is a person assigned to keep watch over a place or area.