One of three kinds of quasiparticle (the other being the spinon and orbiton) that electrons in solids are able to split into during the process of spinu2013charge separation, when extremely tightly confined at temperatures close to absolute zero.
Definition #2 for "holon"
The term "holon" is a structural family therapy term that implies the part and whole inevitably connected. Every holon is both a part and a whole, e.g.: an individual is part of a family, which is part of an extended family, which is part of a community, etc.