This thing where companies can use custom definitions of words in order to intentionally build ambiguity into their agreements is designed to induce just this type of problem. Words have meaning outside these agreements and that outside meaning influences people's interpretation of the agreement. Words are, unfortunately, also ambiguous. So when we make these agreements we allow them to add more detail to definitions in an effort to clear up that ambiguity, but we end up with people trying to argue blatant contradictions like "any reasonable person would understand that own doesn't mean own"