expression — slang, informal
denoting completion of a task, ease of completion, or satisfaction.
The phrase Bob's your uncle is likely a preservation from British English, possibly Cockney English, yet one that is not used in distinct ways in Canada. According to internet searches the expression is used in many former British colonies (see Chart 1). The term is used in ways characteristic of informal speech in Inner Circle varieties more generally (Inner Circle as defined by Kachru (1985), the countries that have predominantly first language speakers of English, usually the UK, Canada, the US, Australia, New Zealand). Many theories exist as to the origin of the phrase, a popular one being that it refers to the appointment of Arthur Balfour to the position of Chief Secretary of Ireland by his uncle Robert Cecil (see, e.g. the 1997 quotation). The origins, however, remain unknown. OED-3 lists the earliest citation for Bob's your uncle from Partridge's 1937 slang dictionary (see OED-3, s.v. "Bob (n7, 3.) - Bob's your uncle").
See also COD-2, s.v. "Bob", which is marked "Cdn & Brit.".
- Used in many Inner Circle varieties of English. Not meeting any of the requirements of Canadianness in DCHP-2 (see Dollinger 2015c).
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Chart 1: Internet Domain Search, 9 Oct. 2013