electrovalent bond
noun [ C ] physics specialized uk/iˌlek.trəʊˌveɪlənt ˈbɒnd/ us/ilektroʊˌveɪlənt ˈbɑːnd/
电价键，离子键
the way in which two atoms are joined together when one atom loses an electron to form a positive ion, and the other gains an electron to form a negative ion