- a fluid in the body cavities and tissues of invertebrates, in arthropods functioning as blood and in some other invertebrates functioning as lymph.
- The blood and lymph considered as a circulating tissue.
- The circulatory fluid of invertebrates, including all arthropods and most mollusks, that have an open circulatory system. Hemolymph is analogous to blood and lymph in vertebrate animals and is not confined in a system of vessels. Hemolymph consists of water, amino acids, inorganic salts, lipids, and sugars. See more at circulatory system.