Where does “onco-” come from?

onco- (Latin) comes from Ancient Greek ὄγκος, from Proto-Italic onkos, from Proto-Indo-European h₂ónkos, from Proto-Indo-European -os — Creates action nouns or result nouns from verbs;...

onco- (Latin): tumor

Definitions

tumor

Ancestry of “onco-”, step by step

Step	Language	Word	Meaning
1	Ancient Greek	ὄγκος	bulk, volume, mass, heap, weight; tumor;...
2	Proto-Italic	onkos	—
3	Proto-Indo-European	h₂ónkos	bend, turn
4	Proto-Indo-European	-os	Creates action nouns or result nouns from verbs;...

Every word from Proto-Indo-European -os →Every word from Proto-Indo-European h₂ónkos →Every word from Proto-Italic onkos →