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Synonyms

intruder

British  
/ ɪnˈtruːdə /

noun

  1. a person who enters a building, grounds, etc, without permission

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

During the summer of 2018, when Stormy was still a nestling, “an adult male intruder showed up to the nest and with great tenacity, refused to leave,” wrote Friends of Big Bear Valley.

From Los Angeles Times • Mar. 3, 2026

K-pop star Nana helped overpower a home intruder and is recovering in hospital after suffering injuries during the tussle, South Korean police said on Sunday.

From Barron's • Nov. 16, 2025

It said speculation about the gorillas had led to more break-ins, with the animals suffering distress due to the triggering of its intruder alarms.

From BBC • Oct. 18, 2025

The adjuvant is a substance that activates the immune system to recognize the antigen, treat it as a foreign intruder and eliminate it.

From Science Daily • Oct. 13, 2025

Finally, as the intruder reached the edge of the first row, he stopped creeping, squatted, and looked forward toward the stage — toward Kira, Jo, and Thomas — with a grin.

From "Gathering Blue" by Lois Lowry