1. coralline - Noun
2. coralline - Adjective
Composed of corallines; as, coralline limestone.
A submarine, semicalcareous or calcareous plant, consisting of many jointed branches.
Formerly any slender coral-like animal; -- sometimes applied more particulary to bryozoan corals.
Source: Webster's dictionaryCoralline algae deposit calcium carbonate in their cell walls and form a hard crust on the substrates where they grow, helping to build and stabilize reefs. Source: Internet