is recorded from 1917. The sense of "opening in a machine for a coin to be inserted" is from 1888 (slot machine first attested 1891). The sense of "position in a list" is first recorded 1942; verb sense of "designate, appoint" is from 1960s. Slot car first attested 1966.
slot"bar or bolt used to fasten a door, window, etc.," c.1300, from M.Du. or M.L.G. slot (cf. O.N. slot, O.H.G. sloz, Ger. Schloss "bolt, bar;" O.S. slutil "key"), from P.Gmc. stem *slut- "to close" (cf. O.Fris. sluta, Du. sluiten, O.H.G. sliozan, Ger. schliessen "to shut, close"), from PIE base *klau-
"hook, peg" (cf. Gk. kleis "key;" L. claudere "to shut, close," clavis "key," clavus "nail;" see
close (v.)).