supply (v.)

late 14c., supplien, "fill (something) up, complete; make up for, compensate for," from Old French soupplier "fill up, make full" (Modern French suppléer) and directly from Latin supplere "fill up, make full, complete," from assimilated form of sub "up from below" (see sub-) + plere "to fill" (from PIE root *pele- (1) "to fill").

The meaning "furnish, provide what is wanted" is recorded by 1520s. With with, before that which is provided, by 1580s. Related: Supplied; supplying.

early 15c., "assistance, relief" (a sense now obsolete); c. 1500 as "act of supplying what is wanted," from supply (v.). The meaning "that which is supplied, quantity or amount of something provided" is attested from c. 1600. Also "person who temporarily takes the place of another" (especially a minister or preacher), from 1580s.

In the political economy sense of "amount or quantity of any commodity on the market and available for purchase" (corollary of demand (n.)) it is by 1776; supply-side (adj.) in reference to economic policy is attested from 1976, from the noun phrase, which is attested by 1922.

Supplies "necessary provisions held for distribution and use" is from c. 1650. A supply train (1860) carries provisions and war gear to an army in the field.