The most common and most likely answer to this crossword clue is the 3 plus 4 letter word RAT TRAP
I've seen this crossword clue in The Daily Telegraph
R
A
T
T
R
A
P
More clues leading to the result RAT TRAP
- Some sailor upset pest controller
- Target of this perhaps bit sailor from behind?
- Piece sailor set up that catches ship’s deserters
- Reversed role with sailor as pest controller
- Two artists quietly drinking dry type of gin
- Some seaman upset in difficult situation
- Exterminator’s equipment uses tartar sauce laced with poison, to begin with
- Unpleasant situation caused by rejecting separate pitch
- Split and separate over a difficult entangling situation
- Predicament in desert associated with role reversal
Buddy explains!

The straight part
We know that "Nasty corner" is the straight/definition part of the clue. The straight part is often a synonym or definition, in this case nasty corner = rat trap.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.