Where does “-diol” come from?

-diol (English) comes from Portuguese di-, from Ancient Greek δίς, from Proto-Indo-European dwís, from Proto-Indo-European dwóh₁ — two.

Ancestry of “-diol”, step by step

StepLanguageWordMeaning
1Portuguesedi-di- two, twice or double
2Ancient Greekδίςtwice, doubly, again
3Proto-Indo-Europeandwístwice, doubly; in two
4Proto-Indo-Europeandwóh₁two
Every word from Proto-Indo-European dwóh₁ →Every word from Proto-Indo-European dwís →Every word from Ancient Greek δίς →