zwitterion /ˈ(t)swidərˌīən, ˈ(t)swɪdərˌaɪən 
/ ▸ noun Chemistry a molecule or ion having separate positively and negatively charged groups.
– DERIVATIVES zwitterionic /ˌ(t)switərīˈänik/ adjective – ORIGIN early 20th century : from German, from Zwitter ‘a hybrid’ + Ion ‘ion’.
EnglishOxford New American Dictionary
