To be lacking legitness and or being unlegit.

When your friend nails a sweet scooter trick, it is called legitness

a shortened form of the word "legitimate". however, this term is nowhere near the real meaning of "legitimate", since it is commonly used to describe things as cool or extremely awesome.

Short for "legitimate". NOT short for "legitimately" which is a totally different word. The difference is roughly the same as between "good" and "well" – in case you cared. An extremely popular yet badly understood filler word.

When something is so legit (real, authentic) that the only word that could possibly describe it is "legitness".

A word used to describe something that was super duper cool. Originally popularized in a Vine, this word has become a common part of many young people's vocabularies.

Real.
Meaning: Not fake or Real(Cool).