Where does “deisyfu” come from?

deisyfu (Welsh) comes from Welsh -u, from Middle Welsh -u, from Proto-Brythonic -oβ̃ — Forms verbal nouns, originally from thematic...

Ancestry of “deisyfu”, step by step

StepLanguageWordMeaning
1Welsh-uimpression, imprint
2Middle Welsh-u—
3Proto-Brythonic-oβ̃Forms verbal nouns, originally from thematic...
Every word from Proto-Brythonic -oβ̃ →Every word from Welsh -u →Every word from Middle Welsh -u →