Where does “couldnae” come from?

couldnae (English) comes from English could, from English ICH, from English ichthyophthiriasis, from English Ichthyophthirius, from Ancient Greek ἰχθύς, from Ancient Greek ἀετός, from Proto-Hellenic ayyetós, from Proto-Indo-European h₂ewyetós — bird.

Ancestry of “couldnae”, step by step

couldnae traces back through two separate lines of ancestry.

via English could

StepLanguageWordMeaning
1Englishcouldsimple past tense of can; conditional of can;...
2EnglishICHInitialism of intracranial hemorrhage; Initialism...
3EnglishichthyophthiriasisA parasitic infection of freshwater fish caused...
4EnglishIchthyophthirius—
5Ancient Greekἰχθύςfish
6Ancient Greekἀετόςeagle; the constellation Aquila; omen
7Proto-Hellenicayyetós—
8Proto-Indo-Europeanh₂ewyetós—
9Proto-Indo-Europeanh₂éwisbird

via English nae

StepLanguageWordMeaning
1Englishnae—
Every word from Proto-Indo-European h₂éwis →Every word from Proto-Indo-European h₂ewyetós →Every word from Proto-Hellenic ayyetós →