needful (adj.)

c. 1200, niedfulle, "necessary, needed, useful," also "in want, poor, hungry, starving, having or exhibiting need or distress," from need (n.) + -ful. Meaning "characterized by need" is from mid-13c. From mid-14c. as "indispensable, necessary," also "urgent, demanding attention."

As a noun, "the poor," from c. 1200. The meaning "what is necessary" is from 1709. The colloquial sense of "cash" is recorded from 1774 in phrase the needful "ready money." Related: Needfully; needfulness.