va·lencyBrE/ˈveɪlənsi/NAmE/ˈveɪlənsi/noun[C, U] (va·lencies) (also va·lenceBrE/ˈveɪləns/NAmE/ˈveɪləns/especially inNAmE) (chemistry化学) ameasurementofthepowerofanatomtocombinewithothers, bythenumberofhydrogen atoms it can combine with or displace价;化合价;原子价◆Carbonhasavalencyof4. 碳的化合价是 4 价。