сердцheart+еforms verbs meaning “become or acquire a quality”+биto hit, to beat+ениaction or process nominalizer+еsingular neuter nominative/accusative
noun · neuter singular · nominativeRare#44,098
heartbeat, heart palpitations
RU: После бега у меня началось сильное сердцебиение.
EN: After running, I developed strong heart palpitations.