The definition of an intrusion is an unwelcome interruption or a situation where somewhere private has an unwelcome visit or addition.(noun)
When you are having a quiet nap in your backyard and your neighbor's dog comes in uninvited and jumps all over you to wake you up, this is an example of an intrusion.
See intrusion in Webster's New World College Dictionary
Origin: ME < OFr < ML intrusio < L intrusus: see intrusive
See intrusion in American Heritage Dictionary 4
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