Out of curiosity, this is from the OED but notice the oh-so-American idea of churning verbs/nouns/adjectives (strikeout at will) outta each and every word, in round-tabler, for one. Jeezzz...

Round Table, n.
Also round table, Table Round.
1. a. The table, celebrated in mediæval legend, round which Arthur and his chosen knights were supposed to have sat, and which was made round so that there might be no pre-eminence or rivalry.
The earliest mention of the table is that in Wace's Roman de Brut (1155). From at least the 15th century (see quot. 1485) the name has been given to a large circular table preserved at Winchester, bearing the names of Arthur and his most famous knights.
b. In Knight (etc.) of the Round Table.
c. The body of knights of this order.
d. A meeting or assembly of Arthur's knights and nobles. Obs.
e. attrib., as Round Table cycle, hero, knight, legend, etc.
2. An imitation of Arthur's Round Table as an institution; an assembly of knights for the purpose of holding a tournament and festival, esp. that instituted by King Edward III in 1345.
The statements in Dugdale, Warton, etc., in regard to the tournament held by Mortimer at Kenilworth in 1279 are based on misunderstandings of the older authorities (see Wykes in Ann. Monast. (Rolls) IV. 281-2 and Rishanger Chron. 94).
b. (See quot.) Obs.
The quotation is a direct translation from Walsingham Historia Brevis (1574) 154.
3. A name applied locally to various natural or artificial antiquities, freq. reputed to have associations with King Arthur.
4. (Freq. with lower-case initials.) Used generally (alone or as attrib. phrase) to denote a number of persons seated round a circular table, or imagined as forming a gathering of this kind; spec. an assembly of people for a conference or discussions at which all participants are accorded equal status (in this sense freq. attrib.). Also transf., a collection of opinions or remarks on a particular subject.
5. A formal association whose members meet regularly for discussion, spec. an organization (or a branch of it) founded in 1927, in which professional people between the ages of 18 and 40 hold discussions, debates, and similar activities, and undertake community service and the promotion of international understanding. Also allusively as adj., designating the qualities or characteristics associated with the Round Table or its members.
Hence round-table v., to take part in a round-table conference; round-tabler.
The use in quot. 1923 is with allusion to the periodical The Round Table (see quot. 1910 under sense 4 above).