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The noun hitwoman (plural: hitwomen) designates:
– (literally): a woman who works as a hired killer;
– (figuratively): a woman who carries out a particular task—especially one involving forceful or underhanded methods—effectively and ruthlessly.
The noun hitwoman was probably coined after hitman (plural: hitmen), designating:
– (literally): a man who works as a hired killer—cf hatchet man;
– (figuratively): a man who carries out a particular task—especially one involving forceful or underhanded methods—effectively and ruthlessly.
In both hitwoman and hitman, the noun hit designates a murder planned and carried out by a professional killer at the behest of someone else.
These are, in chronological order, the earliest literal uses of the noun hitwoman that I have found—they all refer to cinema films and to television films and series:
1-: From a review of The Sting (1973), a U.S. film starring Paul Newman, Robert Redford, Robert Shaw, and Dimitra Arliss as Loretta Salino, a contract killer—review by Sam Pendergrast, ‘Oxford Editor’, published in the Journal-News (Hamilton, Ohio, USA) of Friday 3rd May 1974 [page 23, column 1]:
If Newman is so smart why isn’t he rich; and if Shaw has all that muscle how come he’s easily faked out? And how on earth does a plain waitress in a greasy-spoon café get involved as a “hit-woman”; and if she is one, why doesn’t she do a better job of it?
2-: From Local Films, by Alexander Walker, published in the Evening Standard (London, England) of Monday 2nd September 1974 [page 19, column 6]—the reference is to the U.S. film For Pete’s Sake (1974), starring the U.S. singer, actress and film director Barbra Streisand (born 1942):
RANK CINEMAS are screening the new Barbra Streisand comedy in which she tries to raise the cash to send her taxi-driver husband through college and finds it involves her as an amateur prostitute, hit-woman for the Mafia and smuggler of “hot” cattle from Texas.
3-: From Time Slot Makes Or Breaks TV Program, by Ray Benson, published in The Columbia Record (Columbia, South Carolina, USA) of Saturday 7th September 1974 [Entertainment Week: page 1-B, column 5]—the U.S. actress Yvette Mimieux (1942-2022) wrote, and starred as a contract killer in, the U.S. television film The Deadly Touch, known as Hit Lady (1974):
Connie Stevens finally gets on with “The Sex Symbol” (Sept. 17), and Yvette Mimeux [sic] as a “hit-woman” in “The Deadly Touch” is something else.
4-: From the television programmes for Saturday 14th to Friday 20th September 1974, published in The Galion Inquirer (Galion, Ohio, USA) of Friday 13th September 1974 [page 3, column 5]:
“The Most Deadly Species” is found on ABC’s “The Streets of San Francisco” [Thursday 19th] at 9. Brenda Vaccaro guest stars as a hired hit-woman who uses romance to carry out her assignment.
The earliest figurative use of the noun hitwoman that I have found is from Mrs. Thatcher’s triumph, published in The Vancouver Sun (Vancouver, British Columbia, Canada) of Wednesday 12th February 1975 [page 4, column 1]— this text refers to the Conservative statesman Edward Heath (1916-2005), Prime Minister from 1970 to 1974, and to the British Conservative stateswoman Margaret Hilda Thatcher (1925-2013), Prime Minister from 1979 to 1990:
Margaret Thatcher has accomplished something that ranks high among the more remarkable feats in the long history of British parliamentary democracy.
Without benefit of powerful allies, with most of the media against her, she has confounded the prophets and fought her way to the leadership of Britain’s Conservatives. […]
Mrs. Thatcher’s defeat last week on the first round of the leadership ballot of Edward Heath, party chief for 10 years and former prime minister, was sensational. Her easy victory yesterday over the four men challengers, notably the commentators’ favorite, party chairman William Whitelaw, was something akin to a nuclear explosion in British politics.
Opinion had been widespread that Tory backroom strategists cunningly used Mrs. Thatcher as the hit-woman to dispose of the unpopular Mr. Heath, thus clearing the way to a second-ballot shoo-in for Mr. Whitelaw. Maybe the Tory sachems did figure it that way. If so, the shock they received from the polling results must have been in the megaton range.