How to say "janitor" in Japanese

• 用務員ようむいんCommon
  nounThe most direct equivalent for a janitor or custodian: someone employed to do cleaning and odd maintenance jobs at a school, office, or other building.
• 守衛しゅえいJLPT N1approx.Common
  nounBasically a security guard rather than a janitor; it may be glossed 'janitor' when the person also watches an entrance, but for cleaning duties this is not the word you want.
  守衛しゅえいにとがめられた。↗

  I was challenged by a gatekeeper.
• 管理人かんりにんCommon
  nounCovers a janitor or caretaker in the sense of the person in charge of a building or facility—managing it, taking care of it, and dealing with residents or users.
  管理人かんりにんによってアカウントの認証にんしょうが行おこなわれたあと、あなたに確認かくにんのメールが送おくられます。↗

  You will receive a confirmation email after your account has been activated by an administrator.
• 門番もんばんCommon
  nounA gatekeeper or door guard stationed at a gate; it is only marginally a way to say 'janitor' and is really the word for someone who guards an entrance.
  門番もんばんは門もんを通とおりぬけるのを許ゆるしてくれた。↗

  The gatekeeper permitted me through the gate.

For a building's cleaning/caretaking staff use 用務員; for guarding entrances or people use 守衛; for someone who manages a building or facility use 管理人; 門番 is really about gate guarding.

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

• 用務員ようむいんjanitor
• 守衛しゅえい(security) guard
• 管理人かんりにんadministrator
• 門番もんばんgatekeeper
• 掃除人そうじにんjanitor
• 使丁していservant
• 清掃員せいそういんcleaner
• 掃除屋そうじやcleaner