| any of various glands, as the thyroid, adrenal, and pituitary glands, that secrete certain substances or hormones directly into the blood or lymph; ductless gland. |

A gland that secretes hormones directly into the blood. These glands make up the endocrine system.
endocrine gland n.
Any of various ductless glands, such as the thyroid, adrenal, or pituitary, having hormonal secretions that pass directly into the bloodstream. Also called ductless gland.
| endocrine gland (ěn'də-krĭn, -krēn') Pronunciation Key
A gland of the body that produces hormones and secretes them directly into the bloodstream. In mammals, the thyroid gland, adrenal glands, and pituitary gland, as well as the ovaries, testes, and the islets of Langerhans of the pancreas are endocrine glands. |
endocrine gland
any of the systems found in animals for the production of hormones, substances that regulate the functioning of the organism. Such a system may range, at its simplest, from the neurosecretory, involving one or more centres in the nervous system, to the complex array of glands found in the human endocrine system.
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