How to say "efficient" in Japanese

• 効率的こうりつてきCommon
  na-adjectiveThe direct equivalent of 'efficient': describes methods, systems, or ways of working that achieve results with little wasted time or effort; it evaluates how something is done rather than the person doing it.
  効率的こうりつてきな機械きかいが肉体労働にくたいろうどうに取とって代かわった。↗

  Efficient machinery replaced manual labor.
• 有能ゆうのうJLPT N3approx.Common
  na-adjective, nounIt really means 'capable' or 'competent' — a person with ability who gets things done — so it matches 'efficient' only when the word describes a person, as in 'an efficient worker,' not a method or system.

Choose 効率的 when 'efficient' describes a method, system, or way of working; choose 有能 when it describes a person, where the meaning is really 'capable' or 'competent' rather than efficiency of process.

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

• 効率的こうりつてきefficient
• 有能ゆうのうable
• 能率的のうりつてきefficient
• 無駄のないむだのないeconomical