IPA: /ˈsɛkrɪtəˌɡoʊɡ/
KK: /ˈsɛkrɪtəˌgɔg/
A substance or hormone that causes or encourages the release of another substance, often related to bodily functions like digestion.
Insulin is a secretagogue that helps regulate blood sugar levels by stimulating the pancreas to release more insulin.
Secretagogue is formed from "secre" (from Latin "secreta", meaning to separate or set apart) and "-agogue" (from Greek "agōgos", meaning leader or that which leads). The word refers to a substance that leads to the secretion of another substance, particularly in a biological context.
Think of something that 'leads' ('-agogue') to the 'separation' or 'setting apart' ('secre') of a substance, which is what a secretagogue does.
No commonly confused words.