An intruder is someone who enters a place or situation despite not being invited. If a Girl Scout comes to your door to sell you cookies but ends up trying to watch TV with you, you can call her an intruder.

Some intruders are robbers who break into homes or businesses with the intent to steal things: "The intruder was charged with trespassing, and later was found to have stolen some jewelry and cash." Other intruders might instead invade someone's privacy. Intruder comes from the verb intrude, from the Latin root intrudere, "to thrust in," a combination of in- and trudere, "to thrust or to push."

Definitions of intruder
  1. noun
    someone who intrudes on the privacy or property of another without permission
    synonyms: interloper, trespasser
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    someone who forces their way aboard ship
    crasher, gatecrasher, unwelcome guest
    someone who gets in (to a party) without an invitation or without paying
    an intruder (as troops) with hostile intent
    encroacher, invader
    someone who enters by force in order to conquer
    an intruder who passes into or through (often by overcoming resistance)
    prowler, sneak, stalker
    someone who prowls or sneaks about; usually with unlawful intentions
    pusher, thruster
    one who intrudes or pushes himself forward
    someone who settles on land without right or title
    alien, stranger, unknown
    anyone who does not belong in the environment in which they are found
    foreigner, outsider
    someone who is excluded from or is not a member of a group
    type of:
    persona non grata, unwelcome person
    a person who for some reason is not wanted or welcome
    someone who enters
Word Family

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