Of, relating to, or affecting the rate of muscular contraction, especially of the heart.
chronotropic/ˌkrɒnəˈtrɒpɪk/ /ˌkrɒnəˈtrəʊpɪk/ /ˌkrəʊnəˈtrɒpɪk/
Late 19th century; earliest use found in Proceedings of the American Academy of Arts and Sciences. From chrono- + -tropic, after German chronotrop.
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