Free dictionary online: translation in English, Spanish, French, Italian, Chinese, Russian, definitions, synonyms...
co-driver 
  n one of two drivers who take turns to drive a car, esp. in a rally 

Add your entry in the Collaborative Dictionary.

"Collins English Dictionary 5th Edition first published in 2000 © HarperCollins Publishers 1979, 1986, 1991, 1994, 1998, 2000 and Collins A-Z Thesaurus 1st edition first published in 1995 © HarperCollins Publishers 1995"