Phos is a genus of sea snails, marine gastropod mollusks in the family Nassariidae.

The foot is covered with an auriculate shield-like lobe in front, and ends behind in a single tapering filament.

The shell is cancellated, oblong, acuminated and usually longitudinally ribbed.

The outer lip is striated internally, with a slight sinus near the fore part.

The columella is obliquely grooved, or shows a single plait in front.