Why are two integers called relatively prime when their greatest common divisor is 1?

In number theory, two integers are called relatively prime (or coprime) when their greatest common divisor (GCD) is 1.1

This terminology is used because 1 is the only positive integer that divides every positive integer. When the GCD of two numbers is 1, it signifies that the numbers share no common factors other than 1 (or -1). Essentially, they possess no common prime factors in their respective prime factorizations, meaning they are "prime" relative to one another, even if the individual numbers themselves are not prime numbers.12