1. Directly between two individuals
   "one-on-one instruction";
   - one-to-one
    
2. (sport) being a system of play in which an individual defensive player guards an individual offensive player
   "one-on-one defence";
   - man-to-man

1. (of two persons) in direct encounter
   "preferred to settle the matter one-on-one";
   - person-to-person

1. A private meeting or conversation between two people
   - one-to-one

Derived forms: one-on-ones

See also: case-by-case, individual, item-by-item, private, single

Encyclopedia: One-on-one