Where does “jailor” come from?

Jailor comes from Old French jaioleur, derived from Old French jaiole, which traces to Proto-Germanic gagulaz.

jailor (English): Alternative spelling of jailer

Definitions

Step	Language	Word	Meaning
1	English	jailer	One who enforces confinement in a jail or prison
2	Middle English	gayoler	—
3	Middle English	gayole	—
4	Old French	gaiole	prison; gaol; jail
5	Medieval Latin	gabiola	—
6	Late Latin	caveola	—
7	Latin	cavea	hollow, cavity; cage, den, enclosure, stall,...
8	Latin	cavus	hollow, concave; excavated, channeled;...
9	Proto-Italic	kawos	—
10	Proto-Indo-European	ḱowh₁ós	hollow
11	Proto-Indo-European	ḱewh₁-	to swell; to be strong

jailor — Etymology, Origin & Word History | Etymology Explorer