Where does “quartan” come from?

quartan (English) comes from Old French quartaine, from Latin quartana, from Latin quartanus, from Latin quartus, from Latin quattuor, from Latin caput, from Proto-Italic kaput, from Proto-Indo-European káput — to seize, hold.

quartan (English): A fever whose symptoms recur every four days;...

Definitions

  1. A fever whose symptoms recur every four days;...

Ancestry of “quartan”, step by step

quartan traces back through two separate lines of ancestry.

via Old French quartaine

StepLanguageWordMeaning
1Old Frenchquartainequartan; only used in "fievre quartaine", meaning...
2Latinquartananominative feminine singular of quārtānus;...
3Latinquartanusfourth
4Latinquartusfourth, the ordinal number after "tertius" and...
5Latinquattuorfour; 4
6Latincaputhead; headlike protuberance on an organ or body...
7Proto-Italickaputhead
8Proto-Indo-Europeankáputhead
9Proto-Indo-Europeankap-to seize, hold

via Latin quartāna

StepLanguageWordMeaning
1Latinquartāna
2Latinquartānusfourth e.g. on the fourth day, of the fourth legion etc
3Latinquārtusfourth
Every word from Proto-Indo-European kap-Every word from Proto-Indo-European káputEvery word from Proto-Italic kaput