mekso unary operator: cardinality (#, | |)
Usually should be reserved for use on sets; if applied to group, it is the cardinality of the underlying set (Which is the order of the group)- but it should probably not be applied to an element of a group. Application to a graph is ambiguous: is it the number of vertices or edges, or both, or neither, (if it defined at all)? For a set, each unique heretofore not counted element increments the running subtotal by 1 if the set is countable (small infinite or finite). See: |a|.">cu'a, zilkancu, nilzilcmi, gu'au'i.