preliminary work on or trial production of a play, industrial prototype, etc
adjective
2.
(of a period, model, etc) preliminary; trial
preproduction in American English
(ˌpriprəˈdʌkʃən)
noun
1.
the process of preparing and planning before actual production begins; specif., the choosing of locations, casting of actors, revision of the script, etc. before the actual shooting of a film