From Longman Dictionary of Contemporary Englishbe breathing down somebody’s neckbe breathing down somebody’s neckinformalATTENTION to pay very close attention to what someone is doing, in a way that makes them feel nervous or annoyed How can I concentrate with you breathing down my neck all the time? → breathe
Examples from the Corpus
be breathing down somebody’s neck• I'm already really busy today, and now Paul's breathing down my neck saying he wants the Paris deal completed.• I can't work with you breathing down my neck.• We'd better start sending out those letters soon -- I've had the sales manager breathing down my neck about it all week.• Labour and the Liberal Democrats are breathing down his neck.• Maybe the Assistant Commissioner's wife was breathing down Maxham's neck.• The staff is breathing down your neck.• He would be breathing down your neck all the time. 