Select the most appropriate homonym to fill in the blank. Vishnu checked his…

A homonym is a word that shares the same spelling and pronunciation as another word but carries a different meaning depending on its grammatical function and the context it appears in; the intended sense is identified by examining the verb it pairs with and the role it plays in the sentence.

In "Vishnu checked his watch to see if he was late for school," the verb "checked" needs a noun as its object — something Vishnu can check in order to find out the time. This grammatical slot can only be filled by the noun sense of "watch" that refers to a physical timepiece.

"An act of watching" is also a noun, but it names the activity of observing (as in "keep watch"), not an object one can check for the time. "Look at attentively" and "be careful about" are both verb senses of "watch" (as in "watch the game" or "watch your step"), and a verb cannot serve as the direct object of "checked." "A small timepiece usually worn on the wrist" is the noun sense naming a device that displays time — the only sense that fits both the grammatical slot (object of "checked") and the meaning of finding out whether he was late.

Therefore, "watch" in this sentence means a small timepiece usually worn on the wrist.