Etymology From Middle English girth, gerth, gyrth, from Old Norse gjǫrð, from Proto-Germanic *gerdō, from Proto-Indo-European *gʰerdʰ- (“to encircle, enclose; belt”). Cognate with Gothic 𐌲𐌰𐌹𐍂𐌳𐌰 (gairda), Icelandic gjörð. Also related to German Gurt, English gird, Albanian ngërthej (“to tie, bind, fasten”).
1
A band passed under the belly of an animal, which holds a saddle or a harness saddle in place.
He was standing on the offside of his horse, holding up the flap of his saddle, with the surcingle loosened, and was pointing to the girths. Close to their attachment to the saddle they had been almost cut through with a knife.1929, Baldwyn Dyke Acland, chapter 8, in Filibuster:
2
The part of an animal around which the girth fits.
3
Informal One's waistline circumference, most often a large one.
He's a lusty, jolly fellow, that lives well, at least three yards in the girth.1716 March 15 (Gregorian calendar), Joseph Addison, “The Free-holder: No. 22. Sunday, March 5. [1716.]”, in The Works of the Right Honourable Joseph Addison, Esq; […], volume IV, London: […] Jacob Tonson, […], published 1721, →OCLC:
4
A small horizontal brace or girder.
5
The distance measured around an object; the circumference.
Etymology From Middle English girth, gerth, gyrth, from Old Norse gjǫrð, from Proto-Germanic *gerdō, from Proto-Indo-European *gʰerdʰ- (“to encircle, enclose; belt”). Cognate with Gothic 𐌲𐌰𐌹𐍂𐌳𐌰 (gairda), Icelandic gjörð. Also related to German Gurt, English gird, Albanian ngërthej (“to tie, bind, fasten”).