Tony Cooper:
> As a reader of political news, I often come across "tank", "tanking",
> and "tanked" as a description of some politician's declining approval
> rating. I assume it comes from "into the septic tank".
I would not have guessed that. Places where septic tanks are used are
not ones I would generally think about. But it is a sensible guess,
I guess.
> It's also used in describing plummeting earnings or revenue figures
> in business reporting.
And according to the OED Online, that seems to be where it started.
They group this with tank v.2, though only by way of a draft addition
in 2005. The original meanings of this verb refer to things literally
being put in a tank (whether for measuring, storage, or treatment);
later meanings refer to consuming alcohol, adding fuel to a plane or
car, and figurative variations on this.
They define this newer sense as:
# intransitive. colloquial (originally U.S.). To fall rapidly in
# estimation, value, etc.; to fail; spec. (of an economy or share
# price) to crash.
The earliest cited are from 1979 and 1984 and refer to stock markets.
> Polls were not as much in the news years ago, so the forms of "tank"
> were usually applied to an athlete - usually a boxer - deliberately
> losing.
They list this as sense 6 of tank v.2, and define it as applying
specifically to tennis, or as they put it, to Lawn Tennis. There
are two cites, dated 1976 and 1979.
By the way, the OED Online has two other verbs "tank". Tank v.1 means
to hit, beat up, or defeat soundly; tank v.3 refers to using the armored
war machine.
--
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Toronto | both parties will... notify the other that communication
m...@vex.net | has become impossible..." --memo to university staff
My text in this article is in the public domain.