Quartan
Quartan , adjective
[French quartain, in fièvre quartaine, Latin quartanus, from quartus the fourth. See Quart.]
Of or pertaining to the fourth; occurring every fourth day, reckoning inclusively; as, a quartan ague, or fever.
Quartan , noun
1.
(Medicine) An intermittent fever which returns every fourth day, reckoning inclusively, that is, one in which the interval between paroxysms is two days.
2.
A measure, the fourth part of some other measure.