試作

1. Origins, structure, and basic meaning

• Structure: 試作 (しさく) combines trial 試 and making 作 to denote prototype or trial production.
• Basic usage: It is used for building a test chair or part and checking its fit and operation.

2. Common pitfalls and similar expressions

• Prototype versus final product
  • 試作した marks an experimental stage; it does not guarantee that the design or production specification is final.