Subcommittees
A committee that is a subset of a larger committee is called a subcommittee.
Where the larger group has a name other than "committee" - for example, "Board" or "Commission", the smaller group(s) would usually be called committee(s), not subcommittee(s), and might go by an entirely different name, or substitute "Commission" for "Committee". For example in the sciences, the "International Commission on Stratigraphy" (ICS) a standing working committee is doing organizational work establishing uniform naming and benchmarks in the geologic record and timeline since 1974, all under the auspices of the International Union of Geological Sciences (IUGS). It is technically the "International Stratigraphy Committee" (ISC), which has limited executive committee powers to impanel other subcommittees (also called commissions) to resolve certain matters involving the Geologic time scale—its deliberations and those of its subcommittees must be adopted by the IUGS which meets in a committee-of-the-whole or Congress, every four years or so to deliberate on the subcommittee recommendations and officially adopt or not-adopt such.
From the foregoing, it can easily be seen subcommittees can generally be classified further by the adjectives: "Executive", "Standing", and "Working":
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