From Longman Dictionary of Contemporary Englishnot lift a finger (to do something)not lift a finger (to do something)informalHELP to do nothing to help He never lifted a finger to help me with the kids. → lift
Examples from the Corpus
not lift a finger (to do something)• The Government are not lifting a finger to help the economy of Renfrewshire.• King Charles did not lift a finger to save her. 