1. A two-wheeled carriage drawn by horses harnessed one before the other.
2. A team of carriage horses harnessed in single file.
3. A vehicle, such as a bicycle or kayak, that is designed to be used by two or more people sitting one behind the other.
4. An arrangement of two or more persons or objects placed one behind or adjacent to the other: driving horses in tandem.
1. Being designed to be used by two or more people sitting one behind the other: a tandem bike; a tandem kayak.
2. Having two identical components arranged one behind or adjacent to the other: a tandem axle; a tandem gene.
[Latin, at last, at length; see to- in the Appendix of Indo-European roots.]
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