rest [OE] In the sense ‘to stop working or moving’, rest is an Old English word from a root meaning ‘league’ or ‘mile’—the reference was to a distance after which a person rested. The rest [LME] that means ‘the remaining part’ comes from Latin restare ‘to remain’, also the source of to arrest someone [LME], which you do by stopping them, and restive [M16th]. Like *reprieve, restive is a word whose meaning has been reversed. Its original meaning was ‘inclined to stay still, inert’. It was applied particularly to a horse which remained stubbornly still or shifted from side to side instead of moving on. From this came the current meaning of ‘restless, fidgety’ in the mid 19th century.