机上

1. Origins, structure, and basic meaning

• Structure: 机上 is read as きじょう and means literally on the desk or figuratively armchair and detached from practical experience.
• Basic usage: Literal location appears in 机上に書類を置く, while the figurative sense appears in 机上の議論.

2. Common pitfalls and similar expressions

• Literal and figurative senses
  • Documents are physically on a desk; 机上の議論 criticizes discussion that remains untested in practice.
• Difference from 理論上
  • 理論上 can be neutral, whereas figurative 机上 often points out a lack of contact with real conditions.