From Longman Dictionary of Contemporary Englishsundersun‧der /ˈsʌndə $ -ər/ verb [transitive] literaryBREAK to break something into parts, especially violently SYN split→ See Verb table
Examples from the Corpus
sunder• War and the reality of her marriage had sundered all obligation to her parents' expectations.• During his twenties his father and he were sundered by religion.Origin sunder Old English gesundrian, syndrian 