Refers to an unpleasant odor, often used in formal or written contexts. In everyday speech, 臭い (におい) or 悪臭 (あくしゅう) may be more common.
There's a bad smell coming from the kitchen.
This meat has a stink, so you'd better not eat it.
Compound of 臭 (しゅう, 'smell, odor') and 味 (み, 'taste, flavor'), originally referring to a bad taste or smell. The exact historical derivation is uncertain, but the kanji combination is conventionally associated with an unpleasant odor.