From Arabic ضَرُورِيّ (ḍarūriyy), meaning "indispensable, essential," derived from ضَرُورَة (ḍarūra, "necessity, need"). The word entered Hindi via Persian, which borrowed it from Arabic. The initial Arabic emphatic /ḍˤ/ softened to /z/ in the Persian-to-Hindi transmission, a common pattern in Hindi's large Perso-Arabic vocabulary.

ज़रूरी is one of the most frequently heard adjectives in everyday Hindi conversation, appearing across formal speeches, casual chat, and media alike. Hindi speakers also use the closely related noun ज़रूरत (zarūrat, "need/necessity") — so learning both together is very efficient. Be careful not to confuse ज़रूरी with ज़रूर (zarūr, "certainly/surely") — same root, different part of speech and meaning.