isCoralAtoll

Given a predicate that represents a relationship or action between entities, generate a one-sentence description explaining its meaning.  
# Instructions
Focus on describing the relationship, not the entities themselves. 
# Response Format
Begin the description with \' Indicates...\'

Predicate: isCoralAtoll

Indicates that a location or landform is a coral atoll, i.e., a ring-shaped coral reef (often with islands) encircling a lagoon.