Where does “blæddre” come from?

blæddre (Old English) comes from Proto-West Germanic blādrā, from Proto-Germanic blēdrǭ, from Proto-Indo-European bʰleh₁dʰreh₂(n).

Ancestry of “blæddre”, step by step

Step	Language	Word	Meaning
1	Proto-West Germanic	blādrā	bladder
2	Proto-Germanic	blēdrǭ	bladder
3	Proto-Indo-European	bʰleh₁dʰreh₂(n)	—

blæddre — Etymology, Origin & Word History | Etymology Explorer