The beluga.

(US, colloquial) Any of various colonial tunicates which resemble salt pork when found washed up on the beach.

plural of sea canary

(zoology) Any bryozoan which forms rounded or irregular patches of coral on stones, seaweeds, etc.

plural of sea scurf

A rainbow seen in the spray of the ocean.

plural of sea-bow

Alternative form of seacoal

rock samphire, Crithmum maritimum

plural of sea fan