'arcosolium' originates from Late Latin, specifically the word 'arcosolium', where 'arc-' derives from Latin 'arcus' meaning 'arch' and 'solium' meant 'seat' or 'throne' (used here as a place or platform).

'arcosolium' appears in Late Latin and Medieval Latin descriptions of Christian catacombs and was carried into archaeological and antiquarian English usage largely unchanged as 'arcosolium'.

Initially it referred to an 'arched seat' or 'arched platform' (literal sense of the Latin components); over time it came to denote specifically an arched burial recess in catacombs and tombs.