The story
- Middle English · inherited frominuren
- English todayinure
From Middle English inuren, equivalent to in- + ure (“practise, exercise”).
First known use, by meaning
- from 16th c. To cause someone to become accustomed to something that requires prolonged or repeated tolerance of one or more unpleasantries.
- from 16th c. To take effect, to be operative.
Etymology from Wiktionary, CC BY-SA 4.0.