Sailor supporting a Liberal place of worship (5)
I believe the answer is:
altar
'place of worship' is the definition.
(I've seen this before)
'sailor supporting a liberal' is the wordplay.
'sailor' becomes 'tar' (tar is a kind of sailor).
'supporting' is a charade indicator (letters next to each other) (in a down clue, some letters go below others).
'a liberal' becomes 'al' (I've seen this in other clues).
'tar' put after 'al' is 'ALTAR'.
(Other definitions for altar that I've seen before include "where sacrifices are made" , "Sacred table" , "Site of worship" , "Table used for the mass or eucharist" , "Church focal point" .)