The word Clapton describes the thin wire that is used for the outer wrap - apparently a clapton wire looks the same as Eric Clapton's guitar strings. Big whoop.
There are many variations of 'claptoned' wires, different numbers of core wires, different thicknesses of core wires and outer wrap wire etc, but they are all claptoned wires.
A claptoned wire with more than one core wire will be labelled as a 'fused' clapton and, if you look closely you will notice it has a flat profile. This flat profile means that it will be in contact with more cotton - and, theoretically at least, produce more vapour because of it.
The range of complex wires can be bewildering, but different variations of claptoned wires are probably the most common.
Just to add a bit of confusion there are also 'spaced' variations of claptoned wires where the outer wrapping wire is spaced so you can see the inner cores, or the outer wire will have an S shaped profile. A wire with an S shaped outer wrap will be labelled an Alien lol - even though the outer wrap does the same as a regular clapton. Sometimes ribbon wires are bound together as a core and wrapped - these will be referred to as a 'Staple' wire. If you make Staple from ribbon wire, put a length of roundwire at either side and the put an outer wrap of wire around it this will be a 'Framed' staple.
Builders will make many variations and mix and match the different types of wire builds and give them new, and often very bewildering names - like Staple fused staggertons...
Claptons are the easiest types of complex wire to get your head around.
A basic clapton is a single core wire with a thinner wire wrapped around it. IF it is a 24 gauge core with a 36 gauge outer wrap it will be labelled 24/32.
A fused clapton will have more than one core, a dual 28 core with a 38 outer wrap will be labelled 2x28/38. A triple 28 core with the same sized outer wire will be 3x28/38. A quad core fused using the same gauge wires would be 4x28/38.
With the really complicated wires the labelling will look like it was written by a mad scientist and is as confusing as fck.