Origin

Vinegar is a sour liquid made from fermented grains or fruit, so it makes sense that this character combines 酉, a radical that classifies characters related to alcohol and fermented drinks, with 乍 on the right side. The 乍 component doesn't tell you what vinegar means — it's mainly a sound hint that helped speakers of Chinese remember how to pronounce the character. Together, these parts create a character that points you toward "the sour fermented liquid" in the alcohol family.