1747, "provide with a slot, cut slots in," from slot (n.1). Meaning "drop a coin in a slot" is from 1888. Sense of "take a position in a slot" is from 1940; that of "fit (something) into a slot" is from 1966. Oldest sense is obsolete: "stab in the base of the throat" (c. 1400). Related: Slotted; slotting.