The story
From cy(ano)- + meth- + (guan)idine.
Etymology from Wiktionary, CC BY-SA 4.0.
Today it means: A histamine H₂-receptor antagonist that inhibits the production of acid in the stomach, mainly used to treat heartburn and peptic ulcers, but notorious for causing male impotence. It is a histamine analog, a sulfur-containing derivative of imidazole. Full definition →
From cy(ano)- + meth- + (guan)idine.
Etymology from Wiktionary, CC BY-SA 4.0.