Meaning of MOC in English

k-up [noun] [C] - a full-size model of something large that has not yet been built which shows how it will look or operateShe showed us a mock-up of what the car will look like when it goes into production.Mock-ups are also used when the real thing is not needed.Mock-up aircraft are used when staff are being trained to deal with emergencies.

Cambridge English vocab.      Кембриджский английский словарь.