err [ME] Like error [ME] and erratic [LME], err comes to us from Latin errare, which meant ‘to stray, wander’ but could also mean ‘to make a mistake’. The idea of straying or going off the correct course is still found in erratic, and also in the old term knight errant [ME], so called because they wandered far and wide in search of adventure. Arrant is a Middle English variant of errant, and aberrant [M16th] is literally a ‘wandering away’ from the right path. The proverb to err is human, to forgive, divine is so old that it is found in Latin (humanum est errare, ‘it is human to err’), and also in the 14th-century work of Geoffrey Chaucer: ‘The proverb says that to sin is human, but to carry on sinning is the devil’s work.’ The precise wording that we are familiar with comes from An Essay on Criticism (1711) by the poet Alexander Pope.