One admitted to plead at the bar; one who has been “called to the bar.” The bar is the rail which divides the counsel from the audience, or the place thus enclosed. Tantamount to the rood-screen of a church, which separates the chancel from the rest of the building. Both these are relics of the ancient notion that the laity are an inferior order to the privileged class.
A silk gown or bencher pleads within the bar, a stuff gown or outer barrister pleads without the bar.
Outer or Utter Barrister. This phrase alludes to an ancient custom observed in courts of law, when certain barristers were allowed to plead; but not being benchers (king's counsel or sergeants-at-law) they took their seats “at the end of the forms called the bar.” The Utter Barrister comes next to a bencher, and all barristers inferior to the Utter Barristers are termed. “Inner Barristers.”
The whole society is divided into three ranks: Benchers, Utter Barristers, and Inner Barristers.
An Inner Barrister. A barrister inferior in grade to a Bencher or Utter Barrister.
A Revising Barrister. One appointed to revise the lists of electors.
A Vacation Barrister: One newly called to the bar, who for three years has to attend in “long vacation.”
Source: Dictionary of Phrase and Fable, E. Cobham Brewer, 1894