'nonsense' originates from English combining the prefix 'non-' (meaning 'not') and 'sense' (from Old French 'sens', from Latin 'sensus'), literally meaning 'not sense'.

'nonsense' was formed in early modern English (16th century) by combining 'non-' + 'sense'; 'sense' itself came from Old French 'sens', from Latin 'sensus'.

Initially it meant 'lack of sense' or 'absence of meaning', and it has remained largely the same, extending to describe foolish ideas or speech and as an exclamation of rejection.