Human-in-the-loop
This word is ambiguous word. Recently this word is used in machine learning domain.
https://gyazo.com/3c443d0d33e473cde9e44364b63a4675
human-in-the-loop is everywhere nowaday. For example,
manufacturing
human put material on a machine, the machine fabricate something.
crowdsourcing
human workers are incorporated into software systems (e.g., Amazon Mechanical Turk)
machine learning