dēlīrātĭo (noun F) : id., originally, a going out of the furrow, in ploughing; hence, trop.
* Giddiness, silliness, folly, dotage, madness (very rare): quod vocant lirare, operiente semina, unde primum appellata deliratio est,Plin. 18, 20, 49, § 180: ista senilis stultitia, quae deliratio appellari solet,Cic. de Sen. 11, 36: o delirationem incredibilem! non enim omnis error stultitia est dicenda,id. Div. 2, 43: aliena,Plin. Ep. 6, 15, 4.

s. TLL