When is a Bitcoin Adress considered even or odd?
Are you thinking of public keys? The uncompressed public key consists of two values x and y. For a given x, there are only two possibilities for y, one even and one odd, so sometimes the public key is given just as the x plus a digit to indicate if the corresponding y is even or odd. This is the compressed form of the public key.
Bitcoin addresses are nor even nor odd. I suppose you have been confused by someone, but there is no such concept of an even or odd address.
It might be possible that someone called an address odd, meaning it is a "strange" address. Addresses may be considered strange when they have an extraordinary format. An example may be an address starting with a different character than "1".
(If you would really want to classify addresses as odd or even, you could look at the last bit of the hash160 of the address. But an address being either even or odd doesn't have any implication.)