1 To mount (a horse). [OED2 back v 10.a, →1925 “Now rare”]
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2 To carry (on the back). ?Nth
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3 To address (a letter). [Scots, nIr dial] formerly more widespread, now chiefly Sth, S Midl See Map Cf backing n
1775 in 1855 Gibbes Doc. Hist. Amer. Revol. 1.166 [NJ native in SC], P.S.—I shall back this letter to some unsuspected person that it may be less in danger of surprise from enemies. 1837 Hampshire Gaz. (Northhampton MA) 2 Aug /5, Owing to the pressure of the times / I back this letter with some rhymes. / So, Amos Kendall, hear me crow: / To Boston, this must straitway go! / In Salem street, No. 6, I think, / You’ll get for this the ready chink. 1859 (1968) Bartlett Americanisms 17, Back. . . To back a letter, is Western for to “direct” it. 1862 in 2009 Montgomery–Ellis Corpus Amer. Civil War Letters cAL, Back your letter after this form; Mr. Thomas Worrick Co. C. 34th Regt. Ala. Vols. 1864 Ibid ceTN, I put your letter in a small white envelope and sealed it well and backed it to you. 1895 DN 1.384 wFL. Ibid 396 neIL, IA. 1899 (1912) Green VA Folk-Speech 71. 1902 DN 2.228 sIL. 1903 DN 2.305 seMO, He backed the letter to the wrong post-office. 1907 DN 3.220 nwAR. 1908 DN 3.288 eAL, wGA. 1910 DN 3.436 cwNY. 1915 DN 4.180 swVA. 1917 DN 4.407 wNC. 1926 DN 5.398 Ozarks. 1929 AmSp 5.124 ME, The old folks asked the younger ones to “back” (address) that letter. 1959 VT Hist. new ser 27.124, Back a letter. . . Before envelopes were common, letters were folded and the address written on the back. Obsolete. c1960 Wilson Coll. csKY. 1965–70 DARE (Qu. JJ14, To write a person’s name and where he lives on a letter . . “I’ll mail this letter as soon as I _____it.”) 94 Infs, chiefly Sth, S Midl, Back. 1975 Appalachian Jrl. 2.152 wNC, Many an old timer still speaks of backing a letter. 1998 Atlanta Jrl.–Constitution (GA) 4 Oct sec M 1/1 nwFL, My son down in Alford, Fla., had a neighbor who wasn’t really confident about reading and writing. . . So he asked my son if he would “back” the letter for him. 2000 Shores Tangier Is. 238 Chesapeake Bay, Grandma said she’ll back the Christmas cards (to address the envelopes).
4 with ~up; In logging: to make a back cut n in.
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5 usu with an adv; Of the wind: to shift in a counterclockwise direction. Atlantic, esp coastal NEng Cf backen v
1774 CT Jrl. & New-Haven Post-Boy 22 April /2, He . . met with a Gale of Wind, or rather Hurricane; it came on at E. S. E. and backed round to the N. W. which caused a prodigious high Sea. 1871 Lowell Study Windows 5 MA, Did the Wind back round, or go about with the sun? 1915 Outing 65.616 ME, I bin layin’ there listenin’ to this wind fer an hour. . . I don’t like it much. She’s hauled into the no’theast and backed around into the nor’west. 1951 Hough Singing in Morning 229 seMA, “Backing in” is a phrase that signifies [that the wind is] shifting by a counter-clockwise route. 1965–70 DARE (Qu. B15, When the wind suddenly begins to blow in a different direction, you say it _____) Infs CT17, MA23, 40, 100, NJ22, NC62, VA44, Backed around; NH5, Backed; NC60, Backed up. 1966 DARE FW Addit ceME, When wind backs in from south to east to north, it’s a sign of bad weather. 1975 Gould ME Lingo 2, Back in. . . Most of Maine’s bad weather comes from the northeast, and if a northeast storm clears by backing in it will usually bring one fair day . . and then it will likely storm again.
6 also with ~ up and in phrr back your foot, back a (or your) leg: Used as a command to a cow to make her move her leg out of the way for milking. esp S Midl
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7 To mend temporarily. [Perh from backing piece of cloth used as a foundation or for stiffening]
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