Green’s Dictionary of Slang

1. a writer of any sort, e.g. a clerk, a novelist, a journalist.

1879		N.O. Dly Democrat (LA) 2 Feb. 2/1: Washington has [...] set all the Radical correspondential pen-drivers at work on the coming campaign.
1885		Cheyenne Transporter (Darlington, OK) 15 July 9/2: ‘I should like to write for your newsaper,’ said a brisk young man who asked to see the editor. ‘ Bless you, my boy,’ said the pen-pusher.
1888		Century mag. (N.Y.) XXXVII 580/1: She... looked round on the circle of fresh-faced pen-drivers for explanation .
1895		Eve. Herald (Shenandoah, PA) 12 Mar. 1/4: Paragraphs on Different Subjects Framed by the Pen and Pencil Pushers.
1899		Leighton Buzzard Obs. 3 Oct. 6/1: Carpen eters, tin plate workers, and pen-pushers have got their union.
1900–10		Stephens & O’Brien Materials for a Dict. of Aus. Sl. [unpub. ms.] 118: PEN-PUSHER.
1904		Iron Co. Record (Cedar City, UT) 6 Aug. 2: Penpusher had come home from the office ‘played out’.
1914		Bulletin (Sydney) 15 Oct. 30/3: As a rule, the Rev. Penpusher doesn’t now do much for the city press [...]; but there was a time when three Methodies used to flood one of the Adelaide dailies with leaders and such-like.
1914		Sport (Adelaide) 2 Oct. 5/4: Clarry G, the penscratcher.
1921		Durant Weekly News (Choctaw Nation, OK) 4 Feb. 7: The pen-pusher was all peeved up over some trifle.
1929		J.B. Priestley Good Companions 622: He works in the railway office – pen-pusher.
1936		A.E. Duckett ‘Truckin ’round Brooklyn’ in N.Y. Age 18 Jan. 7/1: Edna and Chester Johnson hold the positions of pen-pusher [i.e. secretary] and Shylock [i.e. treasurer] respectively.
1941		G. Kersh They Die with Their Boots Clean 86: The clurk, the shopwalker, the pen-pusher, the bloke that’s never used his muscles in his life — he’s the bloke I’m sorry for.
1954		Wodehouse Jeeves and the Feudal Spirit 72: Florence tells me that La Morehead is one of the more costly of our female pen-pushers.
1959		C. MacInnes Absolute Beginners 27: ‘Business?’ the poverty-stricken pen-pusher repeated.
1977		G. Melly Rum, Bum and Concertina (1978) 29: Here, however, among my fellow pen-pushers [...] the exercise lacked all realism.
1981		G. Johnston Fish Factory 53: The pen-pushers had picked on a subject that was bound to invoke controversy.
1991		R.G. Barratt ‘Ambos Have to Cop It Sweet’ in What Do You Reckon (1997) [ebook] [P]en-pushers in government departments,.
1998		G. Burn Happy Like Murderers 240: Pen-pushers and briefcase-carrying nosey parkers busybodying and nosey-parkering around.
2000		Indep. Rev. 1 Mar. 1: Jacking in the nine-to-five [...] was once the four o’clock fantasy of every office pen-pusher.
2007		S. Maloney Sucked In 156: He was the hairy-arsed champion of the underdog. We were a cabal of limp-wristed pen-pushers.
2018		G. Disher Kill Shot [ebook] ‘You’re smarter than a bunch of pen-pushers’.

2. a letter-writer.

1928

C. McKay Home to Harlem 231: Who is you’ pen-pusher?