vlakra lujvo

x1 is an etymology of word x2 meaning x3 in language x4

See also valkra, valsi, krasi.

In notes:

blalalavla
x1 is an a-priori word (word with no specific etymology from any language), meaning x2 in language x3
jbokravla
x1 is a native Lojban word (not a borrowing) with meaning/role x2
valkra
x1 is the etymology of word/phrase x2