tandem
noun
°A bicycle with two seats, two sets of pedals, and two wheels; a bicycle-built-for-two.
"we used to ride this tandem"
°An arrangement of two or more objects arranged one behind the other.
"driving cars in tandem"
verb
°One behind the other.
"ride tandem on a bicycle-built-for-two"
adjective
°Together; working as one.
"Their skillful tandem work made the project successful and quick."
synonyms: bicycle-built-for-two, tandem bicycle