The definition of intrude is to butt in where you aren't invited or to become involved in something where you don't belong.(verb)
When you start sharing your opinion in a conversation that you overheard and were not invited to, this is an example of a time when you intrude on the conversation.
See intrude in Webster's New World College Dictionary
Origin: L intrudere < in-, in + trudere, to thrust, push: see threat
See intrude in American Heritage Dictionary 4
verb in·trud·ed, in·trud·ing, in·trudes verb, transitive
Origin: Middle English intruden
Origin: , from Latin intrūdere, intrūs-, to thrust in
Origin: : in-, in; see in-2
Origin: + trūdere, to thrust; see treud- in Indo-European roots.
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