Derived from the Latin alabastrum (noun, neuter), which is a small, pocket-sized bottle. Small in size and inflated in shape, P. alabastrum resembles a flacon. Moreover, being white in colour, it looks as made from alabaster, the soft marble-like mineral.
Fraussen K. 2003. Three new deep-water species of Phos Montfort, 1810 (Gastropoda: Buccinidae) from the South Pacific. Novapex 4(4): 111-118 (look up in IMIS)