What is Barrister?

Legal Definition
A barrister (also known as barrister-at-law or bar-at-law) is a type of lawyer in common law jurisdictions who works at higher levels of court. Barristers mostly specialise in courtroom advocacy and litigation. Their tasks include taking cases in superior courts and tribunals, drafting legal pleadings, researching the philosophy, hypothesis and history of law, and giving expert legal opinions. Often, barristers are also recognised as legal scholars.

Barristers are distinguished from solicitors, who have more direct access to clients, and may do transactional-type legal work. It is mainly barristers who are appointed as judges, and they are rarely hired by clients directly. In some legal systems, including those of Scotland, South Africa, Scandinavia, Pakistan, India, Bangladesh, the British Crown dependencies of Jersey, Guernsey and the Isle of Man, the word barrister is also regarded as an honorific title.

In a few jurisdictions, barristers are usually forbidden from "conducting" litigation, and can only act on the instructions of a senior solicitor, who performs tasks such as corresponding with parties and the court, and drafting court documents. In England and Wales, barristers may seek authorisation from the Bar Standards Board to conduct litigation. This allows a barrister to practise in a 'dual capacity', fulfilling the role of both barrister and solicitor.

In some countries with common law legal systems, such as New Zealand and some regions of Australia, lawyers are entitled to practise both as barristers and solicitors, but it remains a separate system of qualification to practise exclusively as a barrister.
-- Wikipedia
Legal Definition
English law. A counsellor admitted to plead at the bar.

2. Ouster barrister, is one who pleads ouster or without the bar.

3. Inner barrister, a serjeant or king's counsel who pleads within the bar.

4. Vacation barrister, a counsellor newly called to the bar, who is to attend for several long vacations the exercise of the house.

5. Barristers are called apprentices, apprentitii ad legem, being looked upon as learners, and not qualified until they obtain the degree of serjeant. Edmund Plowden, the author of the Commentaries, a volume of elaborate reports in the reigns of Edward VI., Mary, Philip and Mary, and Elizabeth, describes himself as an apprentice of the common law.
-- Bouviers Law Dictionary
Legal Definition
In English law. An advocate; one who has been called to the bar. A counsellor learned in the law who pleads at the bar of the courts, and who is engaged in conducting the trial or argument of causes. To be distinguished from the attorney, who draws the plcadings, prepares the testimony, and conducts matters out of court. In re Rickert, 66 N. H. 207, 29 Atl. 559, 24 L. R. A. 740.
See also
-- Black's Law Dictionary
Legal Definition
A lawyer admitted in England to plead at the bar.
-- Ballentine's Law Dictionary