The term "archaic trespasser" consists of two words that have different meanings. "Archaic" refers to something that is old or outdated, while "trespasser" refers to someone who enters a property without permission. Therefore, synonyms for "archaic trespasser" could include phrases like "outdated intruder," "antiquated invader," or "obsolete violator." Each of these phrases encapsulates the idea that someone or something is entering a space where they should not be, but also suggests that the individual or action is outdated or belongs to another era. Other possible similar terms might include "ancient offender," "prehistoric encroacher," or "obsolete infiltrator".