Etymology From earlier grine, from Middle English grinde, grynde, from Old English grynde (“abyss”) (perhaps also "depression, hollow"), probably related to Proto-Germanic *grunduz; see ground. Later altered under the influence of loin.
1
The crease or depression of the human body at the junction of the trunk and the thigh, together with the surrounding region.
The Mexican levelled nine minutes from time after Steven Gerrard, making his first start since undergoing groin surgery in April, put Liverpool ahead with a 68th-minute free-kick.2011 October 15, Phil McNulty, “Liverpool 1 - 1 Man Utd”, in BBC Sport, archived from the original on 21 Oct 2022:
2
The area adjoining this fold or depression.
He pulled a muscle in his groin.
3
Architecture The projecting solid angle formed by the meeting of two vaults
He got kicked in the groin and was writhing in pain.
My friend […] discovered in his early teen years a passion for both men and opera. He frequented the Met to satisfy his ear but had little knowledge or experience of where to find partners and satisfy his groin.1981 December 5, Michael Bronski, “Coming (Out) to Opera”, in Gay Community News, volume 9, number 20, page 5:
Etymology From earlier grine, from Middle English grinde, grynde, from Old English grynde (“abyss”) (perhaps also "depression, hollow"), probably related to Proto-Germanic *grunduz; see ground. Later altered under the influence of loin.
1
To deliver a blow to the genitals of.
In the scrum he somehow got groined.
She groined him and ran to the car.
2
Architecture To build or furnish with a groin or groins.
The part of the village in which I resided was a grove of cocoa-nut trees, and at night, when the dead leaves were sometimes collected together and burnt, the effect was most magnificent - the tall stems, the fine crowns of foliage, and the immense fruit-clusters, being brilliantly illuminated against a dark sky, and appearing like a fairy palace supported on a hundred columns, and groined over with leafy arches.1869, Alfred Russel Wallace, The Malay Archipelago, volume II, London: Macmillan and Co., page 50:
Down some profound dull tunnel, long since scooped / Through granites which titanic wars had groined.1918, Wilfred Owen, Strange Meeting:
groin
verb
Etymology From Middle English groynen, from a mixture of Old French groignier, grougnier (from Latin grunniō) and Old English grunnian (from Proto-Germanic *grunnōną).
1
To grunt; to growl; to snarl; to murmur.
Such tunges ſhuld be torne out by the harde rootes,c. 1515–1516, published 1568, John Skelton, Againſt venemous tongues enpoyſoned with ſclaunder and falſe detractions &c.
Beares, that groynd continually1596, Edmund Spenser, “Book VI, Canto XII”, in The Faerie Queene. […], London: […] [John Wolfe] for William Ponsonbie, →OCLC, stanza 27: