stomping ground; stamping ground.
The first outnumbers the second by a 3-to-1 ratio in modern print sources. When the first edition of this book appeared in 1998, only one major American dictionary listed "stomping ground." Now almost all dictionaries have it, and about half give it priority over "stamping ground."
It's perfectly idiomatic to say either "stomping ground" or "stomping grounds" — e.g.:
o "Sanchez and Charlton are from Tampa, while Bender hails from Clemson, S.C., head coach Jackie Hadel's old stomping grounds." Scott Kauffman, "Freshmen Serve Up Volleyball Success," Orlando Sentinel, 21 Sept. 1997, at K9.
o "Smith, 51, just completed four consecutive nights at CBGB, her old stomping ground and the birthplace of New York punk." Jim Sullivan, "Patti Smith Finds 'Peace' Outside Rock," Boston Globe, 2 Dec. 1997, at E1.
For information about the Language-Change Index, click here.
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Quotation of the Day: "Every man, in speaking of himself and his wares, exaggerates up; in speaking of his rivals, he exaggerates down. The result is falsehood." E.W. Howe, Ventures in Common Sense 271 (1919).