x1=v1=f1 is a loanword meaning x2=v2 in language x3=v3, based on word x4=f2 in language x5.
Also officialy used to describe words in the Lojban morphological class allocated for use by vonfu'ivla. Due to not being jbosarxe zi'evla is prefered by some. See also pavyfu'ivla, relfu'ivla, cibyfu'ivla, vonfu'ivla, zi'evla, le'avla.