Gland/ɡlænd/ Definition 1 of 2Pro Tip 1/3Inside the Body The term 'gland' in medicine refers to parts inside your body, not seen externally. The pancreas is a gland that is hidden inside the abdomen. Pro Tip 2/3Vital Functions 'Gland' often relates to crucial bodily functions, especially secretion of substances. Adrenal glands play a key role in response to stress. Pro Tip 3/3Not Always Illness The presence of glands is normal, and not necessarily related to diseases. Humans have numerous glands that maintain regular body functions.