4, 5. T respass , encroach , infringe , intrude imply overstepping boundaries and assuming possession of others' property or crowding onto the right of others. To trespass is to pass unlawfully within the boundaries of another's property: Hunters trespass on a farmer's fields. To encroach is to creep, gradually and often stealthily, upon territory, rights, or privileges, so that a footing is imperceptibly established: The sea slowly encroached upon the land. To infringe is to break in upon or invade rights, customs, or the like, by violating or disregarding them: to infringe upon a patent. To intrude is to thrust oneself into the presence of a person or into places or circumstances where one is not welcome: to intrude into a private conversation.