The most common and most likely answer to this crossword clue is the 6 letter word PISSED
P
I
S
S
E
D
Buddy explains!

The straight part
We know that "drunk" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case drunk = pissed.The cryptic/wordplay part
In cryptic crossword there's often an wordplay/cryptic part as well.This part involves a more complex hint, such as an anagram, homophone, hidden word, etc.
Sadly, We don't have an explanation for this specific crossword clue yet.
What does PISSED mean?
PISSED verb- To urinate.
- To discharge as or with the urine.
- Drunk.
- Annoyed, angry.