menkini fu'ivla

x1 are the result of mapping x2 using function x3 (2-ary ka)

The first and second places of x3 correspond respectively to the first and second places of menkini. See also menre, ckini

In notes:

porkifa'u
x1 is a sequence of sequences, whose elements are related respectively by x2 (property, arity is length of x1)