Phosphorescence

Etymology

From "phosphorus" (Greek "phōs," "light," and "phoros," "bearing" — literally "light-bearer") plus "-escence." Phosphorus the element was itself named for its eerie glow.

noun · /fos-fuh-RES-ence/
A lingering glow given off by a material that slowly re-emits light it has absorbed, continuing after the light source is removed.
What it names
The specific "glow-in-the-dark" afterglow — often loosely, and wrongly, applied to glowing sea creatures.
Example
The watch dial held a faint green phosphorescence long after dark.
Related idea
Phosphorescence is a delayed physical afterglow; bioluminescence is fresh light generated by a living organism’s chemistry — the glow of the sea is usually the latter.