(countable, obsolete) A conventional act or constraint
March 15, Frederick Denison Maurice, The Life Of Frederick Denison Maurice Chapter To ____, Having said this, you will not, I trust, suspect me of disliking you for throwing off conventionalisms and speaking to me as a man to a man.
(uncountable, philosophy) The doctrine that logical or mathematical principles are simply the expression of conventions
October 2, Skepticism arrives at conventionalism by way of the claims that the conditions on evidential support cannot be satisfied — Reasons are Supported and No Proposition is Supported only by Endless Regresses , for example— ... but that we must have beliefs in order to carry on.