The suffix is hyphenated to better distinguish the literal-meaning adverb from the intensifierreally.
real-ly (comparativemorereal-ly,superlativemostreal-ly)
- (nonstandard)Alternative form ofreally(“in a way or manner that is real, not unreal”)
1892,The Philosophical Review, volume I, number 5, page541:If it did, there would be no distinction between real and unreal, between what is 'real-ly' presented and 'merely imagined,' between the self and the world, and there would be no such thing as thought.