From Longman Dictionary of Contemporary Englisha pat on the backa pat on the backinformalPRAISE praise for something that you have done well Alex deserves a pat on the back for all his hard work. → pat
Examples from the Corpus
a pat on the back• That was intended to be a pat on the back - as one of several others - for me.• I think you all deserve a pat on the back for your hard work.• The tournament-sponsoring Thunderbirds deserve a pat on the back.• I think we should give Fairclough a pat on the back for his performances in the last few games.• Just a smile or a pat on the back may keep a student working.• It amounts to a pat on the back.• Try starting with a pat on the back to soften the blow of criticism.• No one gets past him without an encouraging word, a pat on the back, a smile.• Now congratulate your loved one and give yourself a pat on the back as well for your own agility around the course. 