From Longman Dictionary of Contemporary Englishin unisonin unisona) TOGETHERif people speak or do something in unison, they say the same words at the same time or do the same thing at the same time ‘Good morning!’ the kids replied in unison. b) PGTOGETHERif two groups, governments etc do something in unison, they do it together because they agree with each other Management and workers must act in unison to compete with foreign business. → unison
Examples from the Corpus
in unison• Management and workers must act in unison to compete with foreign business.• "Good morning!" the kids replied in unison. 