Where does “estival” come from?

estival (Old French) comes from Latin aestivālis, from Latin aestīvus, from Latin autumnus, from Latin auctumnus, from Proto-Indo-European h₃ewǵ- — cold.

Ancestry of “estival”, step by step

StepLanguageWordMeaning
1Latinaestivālissummer
2Latinaestīvussummer
3Latinautumnusautumn, fall; autumn; autumnal
4Latinauctumnusautumn; autumn; autumnal
5Proto-Indo-Europeanh₃ewǵ-cold

Words derived from “estival

Every word from Proto-Indo-European h₃ewǵ-Every word from Latin auctumnusEvery word from Latin autumnus