The term 'Creature Building Reef' is a combination of three words: Creature, Building, and Reef. Creature refers to any living organism, Building is an artificial structure, and Reef is a natural formation of rocks or CORAL. The crossword solution for the term 'Creature Building Reef' is CORAL, which is a type of marine invertebrate that forms large colonies and builds reefs. CORAL reefs are important habitats for many species of fish and other marine life, and they provide protection from storms and erosion.