Where does “bold” come from?

bold (Danish) comes from Old Norse bǫllr, from Proto-Germanic balluz, from Proto-Indo-European bʰel-, from Proto-Indo-European bʰōl-.

bold (Danish): a ball

Definitions

Step	Language	Word	Meaning
1	Old Norse	bǫllr	round object, sphere, ball; testicle
2	Proto-Germanic	balluz	round object, ball; ball of the hand, foot, etc
3	Proto-Indo-European	bʰel-	to sound; to speak, roar, bark; shiny, white; to...
4	Proto-Indo-European	bʰōl-	—

bold — Etymology, Origin & Word History | Etymology Explorer