I am fine-tuning a short note on basic category theory; any such course must introduce monads, and I want to give a bit of history of the subject.

I soon realized that I don't know the precise series of events that led Mac Lane to create the name "monad" instead of the less creative "triple" or "standard construction". Did he coin the term, or did he simply advertize it?

The only reference I can find is a link at the nLab page.