choir / quire are similar-sounding terms with different meanings (referred to as homophones). To better understand the differences, see below for definitions, pronunciation guides, and example sentences using each term. 👇
choir: (noun) a chorus that sings as part of a religious ceremony. (noun) a family of similar musical instrument playing together. (noun) the area occupied by singers; the part of the chancel between sanctuary and nave. (verb) sing in a choir.
quire: (noun) a quantity of paper; 24 or 25 sheets.
choir: k·w·AY·er
quire: k·w·AY·r
(Examples are Wikipedia snippets under the CC ShareAlike 3.0 license. Definitions drawn from WordNet.)