n. pl. de·lir·i·ums or de·lir·i·a (-ē-ə)
1. A temporary state of mental confusion and fluctuating consciousness resulting from high fever, intoxication, shock, or other causes. It is characterized by anxiety, disorientation, hallucinations, delusions, and incoherent speech.
2. A state of uncontrolled excitement or emotion: sports fans in delirium after their team's victory.
[Latin dēlīrium, from dēlīrāre, to be deranged : dē-, de- + līra, furrow; see leis-1 in the Appendix of Indo-European roots.]
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Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
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