Sleepers in monastery abroad losing pants (6,3)

I haven't cracked this one yet — but the brilliant team at Fifteensquared have:

definition: a wagon-lit is a 'sleeper' as a sleeping carriage in a train; Chambers gives 'wagons-lit' as a plural anagram/"pants" of (losing)*, contained "in" WAT=a Thai Buddhist temple or monastery="monastery abroad"