Keyword cannibalization refers to using the same keyword on multiple pages in a manner that the irrelevant page ranks for the keyword.
If you're targeting different keywords on different pages, you're unlikely to have a problem. Just make sure the page you want to rank for the keyword is most clearly the relevant page.
That doesn't mean you can't use a keyword for one page on other. Sometimes it comes in handy for your internal linking structure (linking one page on your site to another using that keyword). Just don't go overboard.