Where does “swythe” come from?

swythe (Middle English) comes from Old English swīþe, from Proto-Germanic swinþa, from Proto-Indo-European swento- — active, healthy.

Ancestry of “swythe”, step by step

Step	Language	Word	Meaning
1	Old English	swīþe	very much, exceedingly, severely, violently,...
2	Proto-Germanic	swinþa	strongly
3	Proto-Indo-European	swento-	active, healthy

swythe — Etymology, Origin & Word History | Etymology Explorer