The term SECRETION ORGAN can be solved by the crossword solution GLAND, which is a five-letter word. Glands are organs in the body that produce and secrete substances such as hormones, enzymes, and other chemicals. They are responsible for many of the body's functions, including digestion, metabolism, and immunity. Glands can be either endocrine or exocrine, depending on the type of secretion they produce. Endocrine glands secrete hormones directly into the bloodstream, while exocrine glands secrete substances through ducts to the outside of the body.