caucus

noun

1. (Canada, Israel, Pakistan, South-Africa, US, Zimbabwe, archaic)A usually preliminary meeting of party members to nominate candidates for public office or delegates to be sent to a nominating convention, or to confer regarding policy.

   “He conferred with Mr. Warren of Plymouth upon the necessity of giving into spirited measures, and then said, "Do you keep the committee in play, and I will go and make a caucus against the evening; and do you meet me."”

2. (Canada, Israel, Pakistan, South-Africa, US, Zimbabwe, archaic)A grouping of all the members of a legislature from the same party.
3. (Canada, Israel, Pakistan, South-Africa, US, Zimbabwe, archaic)A political interest group by members of a legislative body.

verb

1. (Canada, Israel, Pakistan, South-Africa, US, Zimbabwe, archaic)To meet and participate in a caucus.

   “Senator Joseph I. Lieberman of Connecticut said yesterday that he will caucus with Senate Democrats in the new Congress, but he would not rule out switching to the Republican caucus if he starts to feel uncomfortable among Democrats.”

   “The diehard Republicans of Kansas caucused today and delivered a big victory for Mike Huckabee, McCain's remaining serious challenger.”

   “Democratic Sens. Joe Manchin of West Virginia, Doug Jones of Alabama and Kyrsten Sinema of Arizona voted with Republicans against the measure, as did Sen. Angus King of Maine, an Independent who caucuses with the Democrats.”

   “Guardian Australia understands the Liberal states have caucused, and they want the newly elected Morrison government to reboot the Neg, or something very like it.”

2. (Canada, Israel, Pakistan, South-Africa, US, Zimbabwe, archaic, broadly, informal, intransitive)To confer.

   “The protesters caucused nearby to discuss demands.”

3. (Canada, Israel, Pakistan, South-Africa, US, Zimbabwe, archaic, transitive)To bring into or treat in a caucus.

   “Although journalists from the private media were barred from entering the hall, different districts caucused the meeting, discussing the voting centres and other logistics.”