dou·ble·tree 
(dŭbəl-trē′)
(dŭbəl-trē′)n.
A crossbar on a wagon or carriage to which two whiffletrees are attached for harnessing two animals abreast.
- monolithic
- monolithically
- monolog
- monologic
- monological
- monologist
- monologue
- monologuist
- monomania
- monomaniac
- monomaniacal
- monomaniacally
- monomer
- monomeric
- monometallic
- monometallism
- monometallist
- monometer
- monomial
- monomolecular
- monomolecularly
- monomorphic
- monomorphism
- monomorphous
- Monongahela River