Etymology 1

Noun

1. A solid, more or less rigid object with a uniform cross-section smaller than its length.
2. A solid metal object with uniform (round, square, hexagonal, octagonal or rectangular) cross-section; in the US its smallest dimension is .25 inch or greater (US), a piece of thinner material being called a strip.

   Ancient Sparta used iron bars instead of handy coins in more valuable alloi, to physically disencourage the use of money

3. A cuboid piece of any solid commodity.

   bar of chocolate

   bar of soap

4. A long, narrow drawn or printed rectangle, cuboid or cylinder, especially as used in a bar code or a bar chart.
5. A business licensed to sell intoxicating beverages for consumption on the premises, or the premises themselves; public house.
6. The counter of such a premises
7. A similar device or simply a closet containing alcoholic beverages in a private house or a hotel room.
8. An official order or pronouncement that prohibits some activity.
9. Used to stand for some unspecified entity, usually a second entity following foo.

   Suppose we have two objects, foo and bar

10. The railing surrounding the part of a courtroom in which the judges, lawyers, defendants and witnesses stay
11. Short for the Bar exam, the legal licensing exam.

    He's studying hard to pass the Bar this time; he's failed it twice before.

12. A collective term for lawyers; specifically barristers in some countries but including all lawyers in others.
13. The legal profession of lawyers; specifically barristers in some countries but including all lawyers in others.
14. A vertical line across a musical staff dividing written music into sections, typically of equal durational value.
15. One of those musical sections.
16. The crossbar
17. The central divider between the inner and outer table of a backgammon board, where stones are placed if they are hit.
18. An addition to a military medal, on account of a subsequent act
19. A linear shoaling landform feature within a body of water.
20. A ridge or succession of ridges of sand or other substance, especially a formation extending across the mouth of a river or harbor or off a beach, and which may obstruct navigation. (FM 55-501).
21. One of the ordinaries in heraldry; a fess.

    See wikipedia article on the topic:

22. A horizontal pole that must be crossed in high jump and pole vault

Synonyms

• See also Wikisaurus:pub

Verb

1. To obstruct the passage of (someone or something).
2. To prohibit.

   I couldn't get into the nightclub because I had been barred

3. To lock or bolt with a bar.

   bar the door

Synonyms

• See also Wikisaurus:hinder

Preposition

1. Except, with the exception of.

   He invited everyone to his wedding bar his ex-wife.

Synonyms

• apart from, barring, except, except for, excluding, other than, save

Etymology 2