Real Dictionary

bracket
Brackets are a pair of written marks that you place round a word, expression, or sentence in order to indicate that you are giving extra information. In British English, curved marks like these are also called brackets, but in American English, they are c
If you say that someone or something is in a particular bracket, you mean that they come within a particular range, for example a range of incomes, ages, or prices.
countable noun: Brackets are pieces of metal, wood, or plastic that are fastened to a wall in order to support something such as a shelf.
verb: If two or more people or things are bracketed together, they are considered to be similar or related in some way.

bracket in American English
an architectural support projecting from a wall, as a corbel
noun: a support, as of metal or wood, projecting from a wall or the like to hold or bear the weight of a shelf, part of a cornice, etc.
transitive verb: to furnish with or support by a bracket or brackets

bracket in British English
noun: an L-shaped or other support fixed to a wall to hold a shelf, etc
verb: to fix or support by means of a bracket or brackets