To look at something attentively over a period of time.

To keep an eye on something to observe or monitor its behaviors.

किसी चीज पर नजर रखना, उसके व्यवहारों का अवलोकन करना

English Usage: You need to watch the children while they play.

Hindi Usage: तुम्हें बच्चों पर नजर रखनी चाहिए जब वे खेलते हैं।

A device used for telling time.

The act of observing something closely.

किसी चीज का ध्यान से अवलोकन करना

English Usage: The watch of the surroundings was important for safety.

Hindi Usage: आसपास का अवलोकन सुरक्षा के लिए महत्वपूर्ण था।