The definition of one-to-one refers to a situation where every item has a pair.
When there is one teacher for every student, this is an example of a one-to-one ratio.
- permitting the pairing of an element of one group with a corresponding element of another group
- Math. designating a correspondence such that each member of a set has just one partner in another set, and no element in either is without a partner
- Allowing the pairing of each member of a class uniquely with a member of another class.
- Mathematics Relating to or being a correspondence between two sets that assigns to each member of one set exactly one member of the other set.
- A personal relationship between two people.
(comparative more one-to-one, superlative most one-to-one)
- Matching each member of one set with a member of another set.
- There is a one-to-one relationship between days with large cash shortages and his workdays.
- (chiefly UK) Involving direct communication between two people. Used especially to refer to situations in which one person is teaching one other person.
- (mathematics, of a function) Injective, being an injection: having the property that no two elements of the domain are mapped to the same image.