Host

(Namespace: plural glossary)

Type of term	Possible role for a headmate
Synonyms or near-synonyms	Frontstuck, body, core, facade, fronter, gestalt, original
Antonyms or near-antonyms	Alter, fragment, insider, part

A system's host is the headmate who is “supposed” to front. They might not always front, but it is considered problematic for them not to front, and in some cases might happen only in response to stress.

Some systems may not have a host. Some may have more than one host.

A host may be, but is not always, the core and/or original. On the other hand, a host who is not very elaborated beyond simply being the host may be a facade.