The vast majority, but not all. Two counterexamples that come to mind offhand are "cwm" (meaning cirque) and "nth" (first, second, ..., nth). Those are both uncommon enough that they might never occur in the data in question, but we don't really know enough about the problem to make that assumption.

Update: Sorry, I didn't notice at first that bizzach had already mentioned "nth" above. No plagiarism intended ;-)

        $perlmonks{seattlejohn} = 'John Clyman';