Dyad
Definition: two things, considered to be a pair
There are several scientific definitions of this in different disciplines, but they all basically describing two individual things, regarded as a single pair.
The Greek word for “two” is “dio,” from which we got “duo” and “dyas” which means “group of two.”
Why I Looked It Up
Then I glanced towards another part of the room and saw two acquaintances leaning into each other, their foreheads close, one with his hand on the other’s shoulder, bonding with such palpable friendship that they were like a single dyad.