baptistery
Concise Oxford English Dictionary © 2008 Oxford University Press:
baptistery /ˈbaptɪst(ə)ri/ (also baptistry)
▶noun (pl. baptisteries or baptistries) the part of a church used for baptism.
■ (in a Baptist chapel) a sunken receptacle used for baptism by total immersion.
'baptistery' also found in these Oxford entries:

