On grammatical class:

xa'ei'o
binary mekso operator: Let the inputs X1 and X2 be sets in the same universal set O; then the result of this operator applied to them is X1^c \cup X, where for any A \subseteq O, Ac = O \setminus A.
xa'ei'u
binary mekso operator: Let the inputs X1 and X2 be sets in the same universal set O; then the result of this operator applied to them is X1^c \cap X, where for any A \subseteq O, Ac = O \setminus A.