Scottish port involved in Hogmanay revels (3)
I believe the answer is:
ayr
'scottish port' is the definition.
(I've seen this before)
'involved in hogmanay revels' is the wordplay.
'involved in' says the answer is hidden in the clue.
'AYR' is hidden within 'hogmanay revels'.
(Other definitions for ayr that I've seen before include "Scottish resort" , "Scots. town; sounds like song" , "Scottish city" , "Scots port on Firth of Clyde" , "Scottish town, port and racecourse" .)