one-to-one rule
nounUK /ˌwʌn tə ˈwʌn ruːl/
US /ˌwʌn tə ˈwʌn ruːl/
A rule that says each thing can only be matched with one other thing.
The teacher used the one-to-one rule to give every child exactly one book.
RELATED WORDS
OTHER MEANINGS
2. In math, a rule where every input has exactly one output and no two inputs share the same output.
The function follows the one-to-one rule because each number is paired with a different answer.
3. A rule that limits a meeting or lesson to one teacher and one student.
The school has a one-to-one rule for tutoring sessions.
4. A rule that allows only one person to use something at a time.
The library's one-to-one rule means each computer is for one person only.