Related to gland: endocrine gland, parotid gland, pituitary gland, pineal gland, prostate gland, thymus gland. (glănd) n. 1. a. Any of various organs or cell groups, such as the adrenal glands and the salivary glands, that are of endothelial origin and secrete a substance that is used or excreted by the body. b. Any of various organs, such as lymph nodes, that resemble true glands but perform a nonsecretory function.