packhorse · useless

1. Origins, structure, and basic meaning

• Structure: 駄 carries the listed senses of a packhorse and uselessness; the source lists only the on-reading だ.
• Basic usage: In the selected words, 駄目 means not allowed or no good, while 無駄 means waste or uselessness.

2. Common pitfalls and similar expressions

• 駄目 / 無駄
  • 駄目: This word can prohibit an action as not allowed, and it can also judge an attempt or object as useless. Example: ここで写真を撮っては駄目です。
  • 無駄: This word refers to waste or to something failing to serve a useful purpose. Example: 水を出したままにするのは無駄だ。