Endocrine

Part of speech: adjective

Pronunciation: /ˈɛndə(ʊ)kɹaɪn/

Definitions

1. A system of glands that produces and releases hormones directly into the bloodstream to regulate bodily functions
2. A system comprising glands that secrete hormones into the bloodstream, influencing growth, metabolism, and homeostasis throughout the body
3. The network of glands responsible for hormone production and regulation, impacting bodily processes like mood, metabolism, and reproductive functions

Etymology: The key to this word is a single Greek verb: "krinō" meant "to separate" or "to sift," and in physiology it came to mean "to secrete," the idea being that a gland sifts substances out of the blood. Put "endo-" ("within") in front of it and you get something that secretes internally, into the bloodstream rather than out through a duct onto a surface. The word is a French formation, and English took it from there, so the Greek parts were assembled in French before English borrowed the result. The most useful contrast is with "exocrine." Glands that release fluid through ducts, such as sweat glands or salivary glands, are exocrine, with "exo-" meaning "outside." The same verb sits at the heart of both words, so the pair shows the two basic ways the body moves secretions: outward through tubes, or inward into the blood.

Synonyms: hormonal