It's a handy word that easily explains a big gap in your evening of drinking. When you went from drunk and aware, to drunken and unaware, but then got busy with missions that can't be pieced together the next day.
I woke up outside my own house cuddling a wheelie bin, covered in glitter, wearing budgie smugglers over jeans and holding the reins to a miniature horse. Man, I was so drunken last night.
This is used when one is very tired, usually due to excess tiredness, and drunkeness behaviour. Sometimestracks like 'jump around' are involved. One gets awful grumpy.
Short-hand for the word floccinaucinihilipilification, meaning the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language).