Antonyms for the word "most sweet smelling" can vary depending on the context. In general, some of the antonyms for sweet smelling can be harsh, unpleasant, foul, stinking, offensive, or pungent. When talking about fragrances, some of the antonyms for sweet smelling can be woody, musky, smoky, earthy, or spicy. However, it is essential to note that the opposite of sweet-smelling can be subjective and vary depending on personal preferences. For some, the most sweet-smelling scent can be a beautiful floral fragrance, while for others, the smell of freshly baked bread or the salty sea breeze may be their favorite aroma.