- delirium (n.)
- 1590s, from Latin delirium "madness," from deliriare "be crazy, rave," literally "go off the furrow," a plowing metaphor, from phrase de lire, from de "off, away" (see de-) + lira "furrow, earth thrown up between two furrows," from PIE *leis- (1) "track, furrow" (see learn).
