Slot
late Middle English (in the sense ‘slight depression running down the middle of the chest’, surviving as a Scots term): from Old French esclot, of obscure origin.
wiktionary
Middle Low German slot or Middle Dutch slot, ultimately from Proto-Germanic *slutą. Cognate with German Schloss(“door-bolt”), Dutch slot.
The verb is probably from Middle Dutch sluten(“to close, to lock”) (Modern Dutch sluiten(“to close”)).
From Old French esclot, likely from Old Norse slóð(“track”). Compare sleuth.
etymonline
slot (n.1)
late 14c., "hollow at the base of the throat above the breastbone," from Old French esclot "hoofprint of a deer or horse," of uncertain origin, probably from Old Norse sloð "trail" (see sleuth). Original sense is rare or obsolete in Modern English; sense of "narrow opening into which something else can be fitted" is first recorded 1520s. Meaning "middle of the (semi-circular) copy desk at a newspaper," the spot occupied by the chief sub-editor, 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 (n.2)
"bar or bolt used to fasten a door, window, etc.," c. 1300, from Middle Dutch or Middle Low German slot (compare Old Norse slot, Old High German sloz, German Schloss "bolt, bar, lock, castle;" Old Saxon slutil "key," Dutch slot "a bolt, lock, castle"), from Proto-Germanic stem *slut- "to close" (source also of Old Frisian sluta, Dutch sluiten, Old High German sliozan, German schliessen "to shut, close, bolt, lock"), from PIE root *klau- "hook," also "peg, nail, pin," all things used as locks or bolts in primitive structures.
slot (v.1)
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 Oldest sense is obsolete: "stab in the base of the throat" (c. 1400).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.
slot (v.2)
1560s, "to bolt a door," from slot (n.2). Related: Slotted; slotting.
