quartus

Etymology
From (whence 🇨🇬, 🇨🇬 and 🇨🇬), from. Cognate to, from sense “four-sided”. For the phonetic development, De Vaan cites Schrijder positing *kʷtwr̥to- > (with voicing of t) *kʷdwr̥to- > *kʷadworto-, followed by dw > w (cf. ). The resulting *kʷawortos would regularly become quārtus (cf. > ).

Numeral

 * 1)  fourth, the ordinal number after tertius and before quintus