Feverish

wiktionary

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From fever +‎ -ish.

etymonline

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feverish (adj.)

late 14c., "causing fever;" 1630s, "excited, unduly ardent;" 1640s, "having symptoms of fever, having a slight fever," from fever + -ish. Earlier in same sense was feverous (late 14c.). Old English had feferig, feferseoc. Related: Feverishly; feverishness.