From Longman Dictionary of Contemporary Englishcover for somebody phrasal verb1 WORKERto do the work that someone else usually does, because they are not there Who’s covering for you while you’re away?2 PROTECTto prevent someone from getting into trouble by lying for them, especially about where they are or what they are doing → cover→ See Verb table
Examples from the Corpus
cover for • Cindy refused to cover for him when his boss called.• Who's going to cover for you while you're on vacation?