The term 'MEMBER OF A CERTAIN KINGDOM' can be solved by the crossword clue 'ANIMAL' (6 letters). This term is used to describe any living creature that is classified as an ANIMAL, which is a member of the kingdom Animalia. Animals are multicellular organisms that are typically mobile and have specialized sensory organs for detecting their environment. They are heterotrophic, meaning they rely on other organisms for food, and reproduce sexually.