The adjective acrid means a smell or taste that is usually strong and unpleasant.

Synonyms are bitter, pungent, stinging, or harsh.

The word origins from Latin (1712) acer meaning “sharp to the senses, pungent, bitter, eager, fierce”. It also means figuratively, of qualities, “active, ardent, spirited”, as well as “hasty, quick, passionate” or of mind “violent, vehement, subtle, penetrating”. The -id suffix probably is in imitation of acid.

The expired bottled milk gave an acrid taste in his mouth.

The acrid smell of the foods he ordered made him call the restaurant’s manager.

The poisonous plants produced a strong acrid smell.