Biological rings are structures that are found in nature and can be seen in a variety of organisms. The two crossword solutions for the term 'biological rings' are 'areolae' and 'areolas'. Areolae are small, circular areas of tissue that are found in many animals, including humans. They are typically located around the nipples, but can also be found in other areas of the body. Areolas are similar to areolae, but are larger and more distinct. They are usually found around the nipples, but can also be found in other areas of the body.