the heartbeat of somethingAmerican EnglishAmE the main origin of activity or excitement in a place or organization 某事物的中心[核心]the heartbeat of something• The timeless street has been the heartbeat of popular music, and source of countless classics.• Broadway has long been the heartbeat of popular music and the source of countless classics.• Trondur had compared the movement to the heartbeat of a great animal.
→ the heartbeat of something at heartbeat(3)