The mesh matching number represents the percentage of elements that have a direct partner on the other side. The example below shows an example of good reciprocal mesh matching: where element 1 matches with element 2, and element 3 matches with element 4:
The next example below shows bad reciprocal matching. Element 1 matches with element 2, but element 2 matches with element 3 also:
小弟愚见,第二例中就是matcing,但没有reciprocal matching.