Not trying to pick a fight over the use of "EDC" since a lot of folks seem bothered by a perception of misuse. But let me explain why a broad use of that term is OK by me.
As an adjective -- "this is my EDC knife" -- I take the use of the term to mean simply that the particular knife is carried in the ordinary course of an ordinary day. There may be a number of knives in a collection that qualify for that ordinary use, whether because of weight or blade length or other factor that makes for easy carry. That kind of "EDC" knife is being distinguished from other special use knives (maybe a large camping or hunting knife, specialty switchblade, filet knife) that is not typically carried in the ordinary course. I'm not sure anyone on this board has a single knife that they carry every single day of their lives to the exclusion of all other knives. I have a bunch of Izulas that I will occasionally carry (usually for a walk in the woods), but I can't categorize them as any kind of "EDC" knife for myself.
As a verb -- "I EDC this knife" -- I take the use of the term to mean "carry often in the ordinary course". Again, the distinction is simply between that class of knives and other knives NOT carried in the ordinary course. If you're a jungle guide, you may "EDC" a machete. Most of us "EDC" some category of smaller knife (which might still be relatively large, depending on who is carrying for what purpose). But the reference is still to a class of knives suitable for and occasionally carried in the ordinary course of an ordinary day.
In any event, as I mentioned, I think many (if not all) of us here own ONLY "SDC" knives -- Some Days Carry knives -- because some days we carry one knife and other days we carry another.