say it: di-LIR-ee-uhm
delirium is a noun meaning "state of violent mental agitation". It carries 2 recorded senses.
state of violent mental agitation
a usually brief state of excitement and mental confusion often accompanied by hallucinations
Forms marked · are formed by the regular rule rather than recorded in the source data. English keeps a few hundred irregulars and the rest follow the pattern, so the rule is right far more often than not — but it is a rule, and the mark says so.
Definitions, synonyms and semantic relations for delirium come from Princeton University’s WordNet. The pronunciation comes from the CMU Pronouncing Dictionary. Commonness is measured against a corpus of everyday English. Full sources and licences.