And who was the person doing the defining - a christian brother of yours, perhaps? E.g., the dictionary definition of "atheist" has always been screwy, simply because I doubt any atheist was ever consulted - it would always be a christian defining the term.
Pantheism is simply all is god. This makes logical sense if you believe in god's omnipresence. Think about that. Otherwise, whence god's omnipresence?
As to personality, pantheism sees ultimate reality as a Self or a concept beyond the duality of personal and impersonal. Your statement of pantheism as being a "denial" of god's personality sounds suspect to me. It sounds rather like the dictionary definition of "atheist" as one who "denied" there is a god.
Sounds like someone is starting with a premise of a personal god, then working from there. I see that more as just prejudice rather than some disinterested methodology.
How about I define theism as "The denial that the universe spontaneously exists and evolves according to innate and immutable attributes (descriptive laws). Does that work for you?