janitor

Chiefly a word of the United States and the Philippines. Speakers elsewhere tend to say caretaker or custodian for the same work. Feminine forms exist, janitress and the rare janitrix, but the plain noun serves for anyone in the job. It is the form to reach for unless a text deliberately marks gender.

Scotland and Hong Kong give the word a narrower beat: the school, and a job that reaches past the mop into keys, deliveries and visitor sign-ins. In Hong Kong's ESF and independent British schools, caretaker is used as well, so the two words share the same role there. Where the building is not a school, the general sense is the one meant.

Here the word sits closest to its root. Latin ianitor meant "doorkeeper," the one who minds a door and decides who passes. For that job today, doorman is the ordinary word. The cleaning and upkeep of the everyday job grew from this older charge of guarding the entrance.

Internet slang at home on 4chan, casting the forum moderator as the person who cleans up after everyone else. It is sometimes an insult rather than always one, and the clipped forms janny and jannie carry the same edge. Users say it about moderators far more than to them, so keep it out of any message you want a moderator to read kindly.