Where does “sothuvad bulbyl” come from?

sothuvad bulbyl (Swedish) comes from Swedish söt, from Old Swedish söter, from Old Norse sœtr, from Proto-Germanic swōtuz, from Proto-Indo-European swéh₂dus, from Proto-Indo-European sweh₂d- — sweet.

sothuvad bulbyl (Swedish): sooty-headed bulbul, (Pycnonotus aurigaster)

Definitions

sooty-headed bulbul, (Pycnonotus aurigaster)

Ancestry of “sothuvad bulbyl”, step by step

sothuvad bulbyl traces back through two separate lines of ancestry.

via Swedish söt

Step	Language	Word	Meaning
1	Swedish	söt	sweet; of the taste of sugar; sweet; not salty;...
2	Old Swedish	söter	sweet
3	Old Norse	sœtr	sweet
4	Proto-Germanic	swōtuz	sweet
5	Proto-Indo-European	swéh₂dus	sweet
6	Proto-Indo-European	sweh₂d-	sweet

via Swedish bulbyl

Step	Language	Word	Meaning
1	Swedish	bulbyl	a bird of the bulbul (Pycnonotidae) family
2	Arabic	بُلْبُل	nightingale

Every word from Proto-Indo-European sweh₂d- →Every word from Proto-Indo-European swéh₂dus →Every word from Proto-Germanic swōtuz →