This study analyzes the meanings of the preposition OFF as used in English phrasal verbs by categorizing them into semantic types and explores Korean verb-oriented counterparts to facilitate learners’ understanding of phrasal verbs. Treating OFF as a single lexical unit with inherent meaning, the study examines its core sense and patterns of semantic extension based on dictionary definitions and principles of a cognitive-semantic approach. The findings show that the prototypical meaning of OFF is separation from a reference point or surface. This core meaning extends, through metaphor and metonymy, to related categories such as departure, removal, and disconnection. These categories are not mutually exclusive but form a continuum reflecting gradual abstraction from physical separation to functional and conceptual domains. In addition, this study investigates how each semantic category of OFF can be more naturally rendered in Korean through verb-based expressions. Given that Korean lacks prepositions and relies heavily on compound and auxiliary verbs, verb-oriented equivalents provide clearer and more intuitive interpretations than adverbial translations. This study thus contributes to both the semantic analysis of prepositions and pedagogical approaches to teaching English phrasal verbs.