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.]
The American Heritage® Dictionary of the English Language, Fifth Edition copyright ©2018 by Houghton Mifflin Harcourt Publishing Company. All rights reserved.
Indo-European & Semitic Roots Appendices
Thousands of entries in the dictionary include etymologies that trace their origins back to reconstructed proto-languages. You can obtain more information about these forms in our online appendices:
The Indo-European appendix covers nearly half of the Indo-European roots that have left their mark on English words. A more complete treatment of Indo-European roots and the English words derived from them is available in our Dictionary of Indo-European Roots.