I actually enjoy the stedman app on iPad, mostly for etymology and pronunciations. There's also the occasional word that is almost so common that I realize I don't know a good definition of it, much like my relationship with much of the English language. Finally, I'd say it's worth every penny to have a reliable source that says I should NOT interpret an EKG as a "winky back". But again, words, etymologies, etc are just an obsession of mine.
If you want a trial of sorts or just to use it for free, I should say this website is confirmed (matches my apps information verbatim) using the stedman dictionary to provide medical definitions: http://www.medilexicon.com/medicaldictionary.php?t=99822
Do NOT buy that dictionary. A couple of PBL facilitators may make you look something up in it during a PBL session, but there is absolutely no reason for you to spend money on actually owning the thing. You'll never use it at home.