One who guards against possible harm to persons or property, often during the night, and who may sound an alarm in the face of threatened danger. In military service a watchman is usually called a guard or sentry.​—Jer 51:12, ftn; Ac 12:6; 28:16; see GUARD.

As a protection against thieves and vandals, persons often were stationed to watch over ripening vineyards or flocks of animals, positioning themselves perhaps in booths or elevated  watchtowers built for that purpose. (2Ki 17:9; 2Ch 20:24; Job 27:18; Isa 1:8) Siege forces attacking fortified places had watchmen or sentries to give their commanders military intelligence. (Jer 51:12) When King Saul was in the field camp with his army he also had personal watchmen whose responsibility was to look out for their king’s welfare.​—1Sa 14:16; 26:15, 16.

Watchmen were often stationed on the city walls and towers to observe those approaching before they got close. (2Sa 18:24-27; 2Ki 9:17-20) At times watchmen made their inspection rounds through the city streets as well. (Ca 3:3; 5:7) Fearful persons, awake during the dangerous hours of the night, might repeatedly inquire of the watchmen if all was well (Isa 21:11, 12), and it was only natural for watchmen themselves to long for the daylight to come. (Ps 130:6) Happy the city that, in addition to the watchmen, had Jehovah watching over it.​—Ps 127:1.

Figurative Use. Jehovah raised up prophets who served as figurative watchmen to the nation of Israel (Jer 6:17), and they, in turn, sometimes spoke of watchmen in a symbolic way. (Isa 21:6, 8; 52:8; 62:6; Ho 9:8) These prophet-watchmen had the responsibility to warn the wicked of impending destruction, and if they failed to do so, they were held accountable. Of course, if the people were unresponsive and failed to heed the warning, their blood was upon themselves. (Eze 3:17-21; 33:1-9) An unfaithful prophet was about as worthless as a blind watchman or a voiceless dog.​—Isa 56:10.