Meaning of “tandem” - Learner’s Dictionary

tandem

noun uk us /ˈtændəm/
in tandem (with sb)

If someone does something in tandem with someone else, they do it together or at the same time:

The police are working in tandem with local charity groups.

[ C ] a bicycle for two people

(Definition of “tandem” from the Cambridge Learner’s Dictionary © Cambridge University Press)