noun
trial stage; experimental phase; prototype stage
Refers to a phase in development where a product, system, or plan is being tested or prototyped before finalization.
この装置はまだ試作段階で、量産は来年からです。
This device is still in the prototype stage; mass production will start next year.
試作段階のソフトウェアにはバグがつきものです。
Bugs are inevitable in software at the experimental phase.
Compound of 試作 (trial manufacture, prototype) and 段階 (stage, phase).