Angiotensin

Part of speech: noun

Pronunciation: /ænd͡ʒɪəʊˈtɛnsɪn/

Definitions

1. A peptide hormone that regulates blood pressure by constricting blood vessels and stimulating aldosterone release from the adrenal glands
2. This substance plays a vital role in cardiovascular physiology through its ability to narrow blood vessels and increase blood volume
3. It acts primarily by raising blood pressure while also influencing electrolyte balance and fluid homeostasis in the body

Etymology: Angiotensin is a coined scientific name, built from pieces that describe what the hormone does and where it was found. The first part, "angio-", comes from the Greek "angeion", meaning vessel, as in blood vessels. The middle part comes from "hypertension", high blood pressure, shortened to "tens". The final "-in" is the standard suffix chemists add to name proteins and peptides, so the whole word reads roughly as "a substance that acts on the vessels to raise tension." The name was made by putting together existing scientific roots rather than by inheriting an old word, which is why it looks so unlike everyday English. Its construction also follows the pattern of "vasopressin", another blood-vessel hormone whose name marks it as a vessel-active compound.