Green’s Dictionary of Slang

a passive homosexual; also attrib.

2002

D. Watt ‘Idiots Impressions’ on Internet Co-op 🌐 There’s a closet encyclopaedia salesman, / Who dresses up as a wellhung woman, / He’s a letterbox fox with a checkerboard ham.

a postman.

1909

J. Ware Passing Eng. of the Victorian Era.

(UK Und.) the sending of fake begging letters.

1812		Vaux Memoirs in McLachlan (1964) 82: Lest the reader should be unprovided with a cant dictionary, I shall briefly explain in succession: viz., the letter-racket [...] Obtaining money from charitable persons, by some fictitious statement of distress.
1823		Egan Grose’s Classical Dict. of the Vulgar Tongue n.p.: Letter Racket. Men or women of genteel address, going about to respectable houses with a letter or statement, detailing some case of extreme distress [...] by which many benevolent, but credulous persons are induced to relieve the fictitious wants of the imposters [...] This is termed the Letter Racket.
1836		A. Thornton Don Juan in London II 175: He directly afterwards took to collecting money, by what thieves term the Letter Racket.

1. (US) anything that provokes nostalgia.

1971

H.E. Roberts Third Ear n.p.: letter from home n […] 2. another black person in a foreign country.

2. (US black) a watermelon.

1971

H.E. Roberts Third Ear n.p.: letter from home n. 1, a watermelon.

1. a phr. used to warn a man his fly is undone or his shirt is out, also used to a woman when her slip is showing.

1855		‘Q.K. Philander Doesticks’ [M.N. Thomson] Doesticks, What He Says 124: Everything looked so grandly gingerbreadly that I hesitated about going in. Little boy in the corner (barefooted, with a letter in the post office) told us to ‘go in’ and called us ‘lemons’.
1907		J.W. Carr ‘Word-List from Hampstead, N.H.’ in DN III iii 192: letter in the post-office, phr. as interj. Shirt-tail visible in a hole in the seat of a boy’s breeches.
1912		H.A. White ‘A Word-List From Central New York’ in DN III:viii 568: Letter in the post office, phr. Used by a boy to inform another that part of his shirt shows through a hole in the pants.

2. said of a woman who is menstruating.

1984

Partridge DSUE (8th edn) 678/2: late C.19–early 20.