How to say "low-grade" in Japanese

• 駄だ
  prefixCovers 'low-grade' as in poor, trivial, insignificant — worthless rather than merely shoddy. It is less common and does not stand alone; learners meet it as part of other words for things of little value.
• 低級ていきゅう
  na-adjective, nounMatches 'low-grade' when the meaning slides toward low-class or vulgar — inferior in rank or tone rather than just badly made. It is less common; it suits contexts where 'low-grade' implies inferior status or coarse taste.
  一生懸命いっしょうけんめい磨みがきました。困こまったのは、意外いがいと低級ていきゅう宝石ほうせきのストックがないことです。↗

  I polished for all I was worth. The trouble is that my stock of low-grade gems was surprisingly low.
• 質の悪いしつのわるい
  expression, prenominal modifierCovers 'low-grade' in the plain sense of poor-quality or shoddy — bad materials or workmanship. This is the form that directly modifies a noun, so it suits phrases describing goods or workmanship as shoddy.
• 質が悪いしつがわるい
  expression, i-adjectiveCovers the same poor-quality, shoddy sense, but as a predicate: use it to state that something is of bad quality, as when commenting on goods or workmanship.

For 'low-grade' meaning simply shoddy or poor in quality, use 「質の悪い」 before a noun or 「質が悪い」 as a statement; 低級 carries a low-class, vulgar nuance, while 駄 is not used alone and means worthless.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

• 駄だpoor
• 低級ていきゅうlow-grade
• 質の悪いしつのわるいpoor-quality
• 質が悪いしつがわるいpoor-quality