coefficient
/ˌkəuɪˈfɪʃnt; ˌkoə`fɪʃənt/ n
1 (mathematics 数) quantity placed before and multiplying another quantity 系数
In 3xy, 3 is the coefficient of xy. 在3xy中, 3是xy的系数.
2 (physics 物) measure of a particular property of a substance under specified conditions 系数
the coefficient of friction 摩擦系数.