Ruin lodgings, housing artist for carnival (5,4)
I believe the answer is:
mardi gras
'carnival' is the definition.
(I know that Mardi Gras is a type of carnival)
'ruin lodgings housing artist' is the wordplay.
'ruin' becomes 'mar' (I've seen this in another clue).
'lodgings' becomes 'digs' (synonyms).
'housing' indicates putting letters inside.
'artist' becomes 'RA' (Royal Academician, member of Royal Academy of Arts).
'digs' placed around 'ra' is 'digras'.
'mar'+'digras'='MARDI GRAS'
'for' acts as a link.
(Other definitions for mardi gras that I've seen before include "Day for 9 acrosses" , "Time for carnival" , "pre-Lent festival" , "Revelry celebrating Shrove Tuesday" , "Shrove Tuesday festival" .)