What is a homonym for sniff?

There isn't a perfect homonym for "sniff" in the sense of a word that sounds exactly the same but has a completely different meaning. However, there are words that are close:

* Sniff (verb) - to inhale air through the nose, often to smell something.

* Snuff (verb) - to extinguish a flame by putting out the embers (e.g., "to snuff out a candle").

* Snuff (noun) - finely ground tobacco that is sniffed into the nose (this is technically a homograph, meaning it is spelled the same but has different meanings).

So, while there isn't an exact homonym, "snuff" comes close in sound and can be considered a near-homonym.