matched pair
nounUK /mætʃt peə/
US /mætʃt per/
Two things that go together because they are the same or fit each other.
She wore a matched pair of red gloves.
OTHER MEANINGS
2. Two people who work well together or look alike together.
The two dancers made a perfectly matched pair.
3. In math, two numbers or items linked by a one-to-one correspondence.
Each sock was a matched pair with exactly one other sock.
4. Two cards of the same rank in a card game.
He won the round with a matched pair of kings.