[1] : The Collaborative International Dictionary of English v.0.48

quartan \quar"tan\, a. f. quartain, in fi`evre quartaine, l.
   quartanus, fr. quartus the fourth. see quart.
   of or pertaining to the fourth; occurring every fourth day,
   reckoning inclusively; as, a quartan ague, or fever.
   1913 webster
see also:
quart 

[2] : The Collaborative International Dictionary of English v.0.48

quartan \quar"tan\, n.
   1. med. an intermittent fever which returns every fourth
      day, reckoning inclusively, that is, one in which the
      interval between paroxysms is two days.
      1913 webster

   2. a measure, the fourth part of some other measure.
      1913 webster

[3] : WordNet (r) 2.0

quartan
     adj : occurring every fourth day especially the fever and
           weakness of malaria; "quartan malaria"

Quartan >> Q Words
Quartan, definition of term: Quartan
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