intruder
in-TROO-der
/ɪnˈtruːdə(r)/
A person who enters a building, grounds, or private space without invitation, permission, or legal right.
An intruder is specifically unwelcome and often enters with malicious or stealthy intent, unlike a simple visitor or guest.
The story behind the word. The word 'intruder' comes from the Latin verb intrudere, which means 'to thrust in' or 'to push into.' This combines in- (into) with trudere (to push or thrust). It originally described someone who forced themselves into a position or office without right, before evolving to mean someone physically breaking into a home.
Word relationships
- trespasser: A legal term for anyone on private property without permission, whereas intruder emphasizes the physical act of entering a building or private space unlawfully.
- interloper: Someone who becomes involved in a place or situation where they are not wanted, often socially, whereas an intruder physically invades.
- guest: An invited visitor, whereas an intruder is entirely uninvited and unwelcome.
- resident: A legal occupant of a home, whereas an intruder has no right to be there.
Commonly confused with
- trespasser: An intruder enters with malicious intent, often into a building, while a trespasser simply enters land without permission.
Word family
- intrude (verb): To enter a place without invitation or permission.
- intrusion (noun): The act of entering a place without permission.
- intrusive (adjective): Causing disruption or annoyance through being unwelcome.
Collocations
- unwanted intruder
- potential intruder
- detect an intruder
- intruder alarm
Example sentences
- "The alarm sounded the moment the intruder stepped onto the pressure-sensitive mat." Describing a security breach scenario.
Memory hook
Think of an 'intruder' as someone who 'in-trudes' (into the room they push) without your permission. An intruder tries to 'intrude' on your 'intrigue'.
When not to use
Do not use 'intruder' for someone who enters a public space during open hours, even if they are unwelcome.
Fun facts
- In ecology, the term 'intruder' is used to describe an animal that enters the established territory of another animal of the same species.
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