one–on–one 
/ˌwʌnɑnˈwʌn/ adjective
/ˌwʌnɑnˈwʌn/ adjective : involving two people who are dealing with or competing against each other directly
▪ a one-on-one meeting/discussion ▪ a one-on-one defense/competition ▪ one-on-one tutoring
▪ a one-on-one meeting/discussion ▪ a one-on-one defense/competition ▪ one-on-one tutoring
— one–on–one adverb
▪ I'd like to talk with you one-on-one. ▪ They will compete one-on-one for the championship.
▪ I'd like to talk with you one-on-one. ▪ They will compete one-on-one for the championship.
