I was recently told that there is no such word as “conclusory,” and the correct word is “conclusional.” Of course, my dictionary includes conclusory but not conclusional, and his dictionary includes conclusional and lacks conclusory.
So, linguists and people of knowledge, arguing from the roots et al., do either of these words exist and if so, what do they mean?
P.S. You may not use dictionary.com for this exercise, as it is “my” dictionary and so not useful in explicating the issue.
Seriously, nobody? I realize it’s not the most earth-shattering question, but, people, if you don’t help me out, I’m going to have to start listening to my mother. She always said I should’ve taken Latin. Or I think that’s what she said. I wasn’t really listening.
Surely my answer is conclusive? 
From Webster’s Revised Unabridged Dictionary (1913 + 1828):
Conclusional is a fossil, conclusory just rare.
“Conclusory” is a legal term that means t
According to one source, “Conclusory” is a legal term that means the opposite of what it sounds like it would mean.