Niche holiday for politicians (6)
I believe the answer is:
recess
I believe this clue is a double definition.
'niche' is the first definition.
(I know that niche can be written as recess)
'holiday for politicians' is the second definition.
(I've seen this before)
(Other definitions for recess that I've seen before include "Small concavity" , "apse perhaps" , "(Political) holiday" , "Period when parliament doesn't sit" , "Alcove - holiday" .)