meaning of xnor

xor means exclusive or, ie a OR b, excluding the case when both are true. but what about xnor, what is the meaning of the word exclusive here? why exclusive nor, instead of not- exclusive or nxor?

Input1 Input2 Output

or
0 0 0
0 1 1
1 0 1
1 1 1

nor
0 0 1
0 1 0
1 1 0
1 1 0

xnor
0 0 1
0 1 0
1 0 0
1 1 0

xor
0 0 0
0 1 1
1 0 1
1 1 0

nxor
0 0 1
0 1 0
1 0 0
1 1 1