A carriage pulled by two or more draught animals (generally draught horses) harnessed one behind the other, both providing the pulling power but only the animal in front able to steer.

(transferred sense) A bicycle or tricycle in which two people sit one behind the other, both able to pedal but only the person in front able to steer.

(figurative) A group of two or more people, machines etc. working together; close collaboration.

(education) A method of language learning based on mutual exchange, where ideally each learner is a native speaker in the language the other person wants to learn.

(medicine) a hollow metal tube containing radioactive material, inserted through the vagina into the uterus for treatment of gynecological cancer.

Together; working as one.

One behind the other.