caucus

Concise Oxford English Dictionary © 2008 Oxford University Press:
caucus /ˈkɔːkəs/

▶noun (pl. caucuses)

• 1 a meeting of the members of a legislative body who belong to a particular political party, to select candidates or decide policy.

• 2 a group of people with shared concerns within a larger organization.

▶verb (caucuses, caucusing, caucused) chiefly N. Amer. hold or form a caucus.

– origin C18: perh. from Algonquian cau'-cau'-as'u ‘adviser’.