| 1. | to be alertly on the lookout, look attentively, or observe, as to see what comes, is done, or happens: to watch while an experiment is performed. |
| 2. | to look or wait attentively and expectantly (usually fol. by for): to watch for a signal; to watch for an opportunity. |
| 3. | to be careful or cautious: Watch when you cross the street. |
| 4. | to keep awake, esp. for a purpose; remain vigilant, as for protection or safekeeping: to watch with a sick person. |
| 5. | to keep vigil, as for devotional purposes. |
| 6. | to keep guard: She was assigned to watch at the door. |
| 7. | to keep under attentive view or observation, as in order to see or learn something; view attentively or with interest: to watch a play; to watch a football game. |
| 8. | to contemplate or regard mentally: to watch his progress. |
| 9. | to look or wait attentively and expectantly for: to watch one's opportunity. |
| 10. | to guard, tend, or oversee, esp. for protection or safekeeping: to watch the baby. |
| 11. | close, continuous observation for the purpose of seeing or discovering something: Their watch for the birds was unrewarding. |
| 12. | vigilant guard, as for protection or restraint: to keep watch for prowlers. |
| 13. | a keeping awake for some special purpose: a watch beside a sickbed. |
| 14. | a period of time for watching or keeping guard: to stand the first watch. |
| 15. | a small, portable timepiece, as a wrist watch or pocket watch. |
| 16. | a chronometer. |
| 17. | Nautical.
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| 18. | one of the periods, usually three or four, into which the night was divided in ancient times, as by the Greeks or Hebrews: the fourth watch of the night. |
| 19. | a person or group that watches, as a lookout, guard, or sentinel: A watch was posted at sunset. |
| 20. | Also called storm watch. Meteorology. an announcement from the U.S. National Weather Service alerting the public that dangerous weather conditions are a possibility and that vigilance and precautionary preparations are advised: hurricane watch, tornado watch. Compare advisory (def. 5), warning (def. 3). |
| 21. | a flock of nightingales. |
| 22. | watch out, to be on one's guard; be cautious: Watch out for cars when you cross the road. |
| 23. | watch over, to guard for protection or safekeeping: She watched over us like a mother hen over her brood. |
| 24. | on the watch, vigilant; alert: The hunter was on the watch for game. |
| 25. | watch oneself,
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"The Hebrews divided the night into three watches, the Greeks usually into four (sometimes five), the Romans (followed by the Jews in New Testament times) into four." [OED]The meaning "small timepiece" is from 1588, developing from that of "a clock to wake up sleepers" (1440). Watchmaker is recorded from 1630; watchtower is attested from 1544.