Interloper/ˈɪntərləʊpər/ Definition 1 of 2Pro Tip 1/3Unwanted Presence Interlopers are not only unwanted but often unexpectedly or sneakily present. He felt like an interloper at her family reunion. Pro Tip 2/3Negative Connotation Often implies the person is interrupting harmony or causing issues in a situation. A disruptive interloper disturbed the peaceful protest. Pro Tip 3/3Not a Member An interloper is usually not a recognized or legitimate part of a group. The club members treated him as an interloper.