These sort of words are called SLANG. Some people believe they're quite harmful for the language.
However, Slang language is becoming very useful nowadays. Everybody uses these kind of words like hangry, adorkable, YOLO, LOL...
Slang language helps us create new concepts and ideas, but there's a lot of slang vocabular in English language. How can we know if a slang word is real and usable? Maybe, you'll be told something like:"If the word isn't in the dicionary, it doesnt exist" How can dicionary editors know every single word in English if it's changing everyday? The question is what makes a word real?
Well, probably the truthis that a word becomes real as soon as aome people can use it and understand it. Personally, I think English is a very rich language and very functional because thanks to this phenomenon we call slang and some other tools which help us originate new words, we can communicate new ideas and concepts which other languages cannot. That's why, thanks to these language mechanisms we can originate neologisms wich doesn't sound in uch a technical way and can be understood by everyone.
This is my message: I encourage you to use the language in the most fascinating way you can without worrying about the rules. English is a language you can play with, not a scienc wich establishes some new rules. We’re human. We love to play with words in creative ways. And in the process, we change the language.
Here, you can hear a speech given by Anne Curzan speaking about this phenomenon.