1. A domed semicircular or polygonal recess, generally at the east end of the choir of a church; any vaulted or semi-vaulted recess.

Nuttall's Standard dictionary of the English language By Nuttall, P.Austin

• asse,
• ase,
• alse,
• ause,
• acsse,
• applse,
• apese,
• thpse,
• hpuse,
• aplle,
• apage,
• azue,
• aps,
• apst,
• appes,
• auser,
• apres,
• asser,
• itse,
• apper

• apsu,
• apache,
• aphis,
• apex,
• apus,
• apiece,
• apace,
• apish,
• appose,
• appease,
• apogee,
• apios,
• apc,
• apis.

The adjective form of the word "apse" is "apsidal".

The plural of the "apse" can be the "apses".

The singular of the "apse" can be the "apse".