[ dɪ'lɪrɪəm ]
■ noun an acutely disturbed state of mind characterized by restlessness, illusions, and incoherence of thought and speech, occurring in fever and other disorders and in intoxication.
Origin
C16: from L., from delirare 'deviate, be deranged' (lit. 'deviate from the furrow'), from de- 'away' + lira 'ridge between furrows'.