地下茎

1. Origins, structure, and basic meaning

• Structure: 地下茎 is read as ちかけい and is a noun for an underground stem that can grow and spread beneath the soil.
• Basic usage: Growth appears in 地下茎を伸ばす, while form appears in 太い地下茎.

2. Common pitfalls and similar expressions

• Root and stem
  • Although it is underground, it is a stem rather than a root.
• Rhizome and underground stem
  • Underground stem is the broad description, while rhizome naturally fits a form that extends horizontally.