Where does “graula” come from?

graula (Late Latin) comes from Latin graulus, from Latin grāculus, from Proto-Indo-European greh₂-k- — croak.

Ancestry of “graula”, step by step

Step	Language	Word	Meaning
1	Latin	graulus	—
2	Latin	grāculus	—
3	Proto-Indo-European	greh₂-k-	croak

graula — Etymology, Origin & Word History | Etymology Explorer