To be nice and confusing, originally (pre Planescape and Spelljammer), there wasn't a prime material plane...there were many prime material planes. They were called the 'Primes', although inhabitants of a world referred to their Prime as 'the Prime Material Plane" or just "the Prime" and all other Primes as "Alternate Prime Material Planes" or "Alternate Primes".
Second edition unified all the 'Primes' into a single 'Prime Material Plane'. The word 'prime' has since fallen off and its just 'Material Plane'. There's no 5e usage of 'prime' [that I've found].
There's a one page article in Dragon #351 that talks about this a bit and ADD's Manual of the Planes talks about it as well.
I hear the term Prime Material Plane alot. What's the difference between the material plane and the prime material plane?
I have no personality.
Their really is not, it's all semantic with no real meaning
Material plane, usually refers to the single word
Where the prime material refers to all material worlds in the forgotten realms cosmology.
But even this is very lose, you can use the first to mean the second all the time, and occasionally the second to mean the first.
My homebrew content: Monsters, subclasses, Magic items, Feats, spells, races, backgrounds
To be nice and confusing, originally (pre Planescape and Spelljammer), there wasn't a prime material plane...there were many prime material planes. They were called the 'Primes', although inhabitants of a world referred to their Prime as 'the Prime Material Plane" or just "the Prime" and all other Primes as "Alternate Prime Material Planes" or "Alternate Primes".
Second edition unified all the 'Primes' into a single 'Prime Material Plane'. The word 'prime' has since fallen off and its just 'Material Plane'. There's no 5e usage of 'prime' [that I've found].
There's a one page article in Dragon #351 that talks about this a bit and ADD's Manual of the Planes talks about it as well.
Guide to the Five Factions (PWYW)
Deck of Decks