機械・器械|きかいkikai[1]atamadaka (head-high)

1. nounmachine; mechanism
   僕ぼくは今日きょうこの機械きかいを試験しけんするつもりです。↗

   I am going to put this machine to the test today.
2. nouninstrument; appliance; apparatusoften 器械
   血圧計けつあつけいが大切たいせつな検査けんさ器械きかいです。↗

   The sphygmomanometer is an important diagnostic instrument.

• SynonymマシンNeutralLoanword for machines; also specifically race cars and racing bikes, as in 「レーシングマシン」. For machines in general, 「機械」 is the more common word.
• Synonym機器ききNeutralCollective term for machines and appliances; common in 「電子機器」「医療機器」. 「機械」 usually refers to individual machines themselves.
• SynonymメカCasualColloquial. Shortened loanword for mechanical devices and parts; as in 「メカに強い」. Common in talk about anime, cars and the like.
• Related器具きぐNeutralImplements and utensils of simpler construction, e.g. 「調理器具」「照明器具」; 「機械」 is usually more complex in structure.
• Related機材きざいNeutralMachinery and materials needed for a job, e.g. 「撮影機材」「建設機材」; stresses a full set of equipment for the work.
• Related計器けいきWrittenWritten/formal. Meters and gauges for measuring length, weight, speed, pressure, etc., as in 「計器盤」; narrower than 「機械」, limited to measuring instruments.
• RelatedメカニズムNeutralLoanword for structure and working principles; also used for abstract things, e.g. 「発病のメカニズム」. The focus is on how something works, not the machine itself.
• Related道具どうぐNeutralGeneral word for tools and implements used in tasks; also figuratively a means, as in 「道具にする」. 「機械」 stresses a device built from multiple mechanisms.
• Related用具ようぐNeutralEquipment for a particular activity; often in compounds like 「掃除用具」「筆記用具」. Leans toward written prose; close to 「道具」.
• Related工具こうぐNeutralTools for working, assembling or disassembling, e.g. 「工具箱」「切削工具」. 「機械」 is the device itself; tools are what you use on it.
• RelatedツールNeutralLoanword for tools and means; also software tools, e.g. 「便利ツール」. Mostly used in computing and business settings.
• RelatedからくりNeutralMechanical contrivances, as in 「からくり人形」; also hidden tricks or schemes, as in 「からくりを見破る」. Usually written in kana.

For ordinary machines, use 「機械」. Use 「機器」 for machinery and equipment as a collective, 「器具」 and 「道具」 for simple implements, 「工具」 for tools used in working on things, and 「メカニズム」 for how something works. マシン, 機材, 計器, 用具, ツール, 絡繰り and メカ each cover more specific ground.

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

1. 作業さぎょう、動力どうりょく発生はっせい、伝達でんたつ、制御せいぎょの4つの機構きこうを組み合くみあわせてできており、仕事しごとなどに使用しようされる装置そうち。
2. 仕掛しかけ。たくらみ。駆け引かけひき。