A composite link is a link that is not a prime link, i.e., it is a link that can be represented as a knot sum of other links.
Composite Link
See also
Composite Knot, Knot, Link, Prime Knot, Prime LinkExplore with Wolfram|Alpha
Cite this as:
Weisstein, Eric W. "Composite Link." From MathWorld--A Wolfram Web Resource. https://mathworld.wolfram.com/CompositeLink.html