Snarl-up on initially tight corner (6)
I believe the answer is:
tangle
'snarl-up' is the definition.
(I've seen this before)
'on initially tight corner' is the wordplay.
'on' is a charade indicator (letters next to each other).
'initially' says to take the initial letters.
'corner' becomes 'angle' (I've seen this before).
The first letter of 'tight' is 't'.
't' put next to 'angle' is 'TANGLE'.
(Other definitions for tangle that I've seen before include "Jumble" , "Complicated mess" , "Get knotted!" , "Confused interwoven mass" , "Confused mess" .)