Nemerteans are commonly referred to as ribbon worms, due to their slender, elongated bodies that can stretch to several meters long. They are also known as proboscis worms because of the proboscis that they use to capture prey. Another synonym for nemertean is rhynchocoel, referring to the fluid-filled cavity that runs the length of their body. In some regions, they are called bootlace worms because of their resemblance to thin shoelaces. The term nemertine is also sometimes used as a synonym for nemertean, particularly in scientific literature. Regardless of what they are called, nemerteans are fascinating creatures with a unique set of biological characteristics that make them an important group to study in marine biology.