quintan

Quin"tan, a. Etym: [L. quintanus, fr. quintus fifth, quinque five. See Five.] Defn: Occurring as the fifth, after four others also, occurring every fifth day, reckoning inclusively; as, a quintan fever. -- n. (Med.) Defn: An intermittent fever which returns every fifth day, reckoning inclusively, or in which the intermission lasts three days.

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