Clue: Interdenominational material welcoming trendy (essentially smug) church offered up (10)
Answer: ECUMENICAL
Explanation: Definition: Interdenominational
A reversal ('offered up' in a down light) of LACINE, an envelope ('welcoming') of IN ('trendy') in LACE ('material'); plus MU ('essentially s**MU**g') plus CE ('church' of England).