Well, guess what. The definition has changed and Zionist now means "people who like Israel killing children". That original definition is the old, inaccurate one now.

Because words are defined by how they're used, and when self identifying Zionists are using the new definition, and everyone else is using the new definition, your "technically that's incorrect" statement means nothing.

The meme is using the word Zionist to mean "people who like Israel killing children" and you, me, and everyone else knows it.