What is…
ague

This archaic old English word means “fever.” It is used in the King James Version only once (Leviticus 26:16). Modern English translations use the word “fever.”

The original Hebrew word is קַדַּ֫חַת (transliteration: qaddachath or kaddah'ath), meaning “fever”, i.e., an inflammatory or burning fever.

In the King James translation of Deuteronomy 28:22 the word is translated “fever.”