Where does “cazerna” come from?

cazerna (Old Occitan) comes from Vulgar Latin quaderna, from Latin quaterni, from Latin quater, from Latin quattŭor, from Portuguese quarto, from Old Portuguese quarto, from Latin quārtus, from Proto-Indo-European kʷeturtos — and.

Ancestry of “cazerna”, step by step

cazerna traces back through two separate lines of ancestry.

via Vulgar Latin quaderna

Step	Language	Word	Meaning
1	Vulgar Latin	quaderna	—
2	Latin	quaterni	four each; four at a time
3	Latin	quater	four times
4	Latin	quattŭor	four; 4
5	Portuguese	quarto	ordinal form of quatro; fourth; quarter; fourth;...
6	Old Portuguese	quarto	quarter
7	Latin	quārtus	fourth
8	Proto-Indo-European	kʷeturtos	—
9	Proto-Indo-European	kʷetwóres	four
10	Proto-Indo-European	kʷe-	and

via Latin quaternus

Step	Language	Word	Meaning
1	Latin	quaternus	four each; four at a time
2	Latin	-nus	-an
3	Proto-Italic	-nos	Creates verbal adjectives from verb stems
4	Proto-Indo-European	-nós	Creates verbal adjectives from roots

Words derived from “cazerna”

Every word from Proto-Indo-European kʷe- →Every word from Proto-Indo-European kʷetwóres →Every word from Proto-Indo-European kʷeturtos →