While 动身 is a straightforward verb, its usage taps into the cultural significance of journeys in China. Historically and today, journeys for education, business, or family reunification (especially during the Spring Festival) are seen as important undertakings. Using 动身 instead of a more casual word like 走 (zǒu) can add a layer of deliberateness and purpose to the act of leaving. It frames the departure not as a simple exit, but as the formal commencement of a trip. Compared to the common English phrase “to leave,” 动身 is closer in feeling to “to set out,” “to depart,” or “to get underway.” While an American might casually say “I'm leaving for New York tomorrow,” using 动身 (我明天动身去纽约) sounds slightly more planned and significant. It conveys that the preparations are done and the journey is now beginning. It’s the verb for the moment you pick up your suitcase and walk out the door.
动身 is a common and useful word, occupying a space between casual and highly formal language.
The most common point of confusion for learners is the difference between 动身 and its close synonym, 出发 (chūfā).