"arch of the foot," mid-15c., apparently from in + step, "though this hardly makes sense" [Weekley]. An Old English word for "instep" was fotwelm. Middle English also had a verb instep "to track, trace" (c. 1400). Old English instæpe (n.) meant "an entrance."
instate
instatement
instauration
instead
instellation
instep
instigate
instigation
instigator
instill
instillation
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