The word 'tangy' originates from the noun 'tang', which entered English in the Middle English period, likely from Old Norse. The original Norse meaning, "point" or "sharp end," evolved in English to describe a sharp, penetrating taste or smell, metaphorically transferring the physical sensation of a point to a sensory experience. The addition of the productive English adjectival suffix '-y' (meaning "characterized by" or "full of") in the 19th century formally created the adjective 'tangy'. Thus, the modern meaning of a strong, sharp flavor directly continues the ancient logic of sharpness moving from a physical to a sensory domain.

The word is a simplex form. It is derived from the noun 'tang', which is of likely Scandinavian origin (e.g., Old Norse tangi meaning "point, spike, tang of a knife"), combined with the adjectival suffix '-y'.