As nouns the difference between bar and bur
is that
bar is a solid, more or less rigid object of metal or wood with a uniform cross-section smaller than its length while
bur is a rough, prickly husk around the seeds or fruit of some plants.
As a verb bar
is to obstruct the passage of (someone or something).
As a preposition bar
is except, with the exception of.
As a proper noun Bar
is a city in Montenegro.