Leader's hideout, old and current, in retreat (9)
I believe the answer is:
editorial
'leader's' is the definition.
(type of newspaper article)
'hideout old and current in retreat' is the wordplay.
'hideout' becomes 'lair' (I've seen this in another clue).
'old' becomes 'o' (common abbreviation eg in OE for Old English).
'and' is a charade indicator (letters next to each other).
'current' becomes 'tide' (sea currents).
'in retreat' says the letters should be written in reverse.
'lair'+'o'+'tide'='lairotide'
'lairotide' in reverse letter order is 'EDITORIAL'.
(Other definitions for editorial that I've seen before include "Newspaper item" , "Article that states a newspaper's opinion" , "Paper's opinion piece" , "Article giving opinion of a newspaper" , "Newspaper article giving the editor's opinions" .)