How to say "parts" in Japanese

• 部品ぶひんJLPT N2approx.Common
  nounThe common word for the physical parts or components of machines, vehicles, and electronic devices, as when ordering a replacement part. This is the word you want for most everyday senses of 'parts'.
  この車くるまの予備よびの部品ぶひんを買かうことができない。↗

  I cannot buy spare parts for this car.
• 部分品ぶぶんひん
  nounA less common synonym of 部品 with essentially the same meaning, met mainly in technical writing. For ordinary talk about the parts of a machine, 部品 is the word you want.
• サブユニット
  nounA loanword meaning 'subunit': a unit that forms part of a larger system or device. It is not a general word for 'parts'; 部品 is the safer choice.

For the parts of machines, vehicles, and appliances, 部品 is the common word; 部分品 is a less common technical synonym, while 「サブユニット」 fits only when 'parts' means the subunits of a larger system.

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

• 部品ぶひんparts
• 部分品ぶぶんひんpart
• サブユニットparts