(a) Slang and colloquial terms are often peculiar to one region and should be enclosed in quotation marks if they are foreign to the normal vocabulary of the intended readers:
Vernacular terms used for effect in administrative documents and reports are treated in the same way.
However, the enclosure of supposed slang or colloquial words in quotation marks is often unnecessary. First, ascertain whether the term is now part of the standard language. If it is, quotation marks are not required. If the term is still a slang term, determine whether using it, rather than a synonym that is standard, is warranted—for rhetorical effect or in order to demonstrate a person’s or group’s speech or style, for example.
(b) Technical terms may be enclosed in quotation marks in non-technical writing:
This practice is often unnecessary, however, in an era when the educated lay reader has some knowledge of modern science and engineering. Depending on the target readership, technical terms may not need special treatment.
(c) Quotation marks can also enclose words used ironically:
Here again, it is often possible to avoid quotation marks by using the preceding text to prepare the reader for the irony.
(d) Words used in a special sense or juxtaposed to terms with which they are not usually associated require quotation marks:
© Public Works and Government Services Canada, 2013
TERMIUM Plus®, the Government of Canada's terminology and linguistic data bank
Writing Tools – The Canadian Style
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