Where does “mustalentäväkoira” come from?

mustalentäväkoira (Finnish) comes from Finnish lentäväkoira, from Finnish koira, from Finnish -nen, from Finnish -inen, from Finnish -uus, from Proto-Finnic -uc — -ness, -hood.

Ancestry of “mustalentäväkoira”, step by step

mustalentäväkoira traces back through two separate lines of ancestry.

via Finnish lentäväkoira

StepLanguageWordMeaning
1FinnishlentäväkoiraAlternative spelling of lentävä koira; flying fox
2Finnishkoiradog; dog paddle; military police
3Finnish-nenForms diminutives nouns or terms expressing...
4Finnish-inen-like, -ous, -y; -en; Creates adjectives from...
5Finnish-uusForms nouns from adjectives, expressing a quality
6Proto-Finnic-uc-ness, -hood

via Finnish musta

StepLanguageWordMeaning
1Finnishmustablack; black horse; Elative singular form of...
2Finnish-ntääFront vowel variant of -ntaa
Every word from Proto-Finnic -ucEvery word from Finnish -inenEvery word from Finnish -uus