1 also attrib: = breaking plow n. esp Plains States
[. . .]
2 = water break n. [Because it breaks the flow of water; despite the semantic similarity to speed breaker n, the regional distribution suggests that they developed independently.] chiefly MD, PA old-fash
1878 Star & Sentinel (Gettysburg PA) 29 Aug /1 (newspaperarchive.com), His horse stumbled over a breaker throwing Mr. Spence to the ground and severely injuring him in the back and side. 1885 Wheeling Reg. (WV) [11 May 4]/6, The front wheels struck a breaker in the road which threw the rear end of the bed up and uncoupled the wagon. 1895 DN 1.385 swPA, Breaker: ridge of earth in hilly part of country road, to throw surface water into side ditches. . . (Other names for same thing: “thank-you-ma’am,” cradle (in-the-road).) 1903 Mail (Hagerstown MD) 25 Sept 2/6, The course has been diverted by a high breaker in the road and the water floods the lands of Mr. Richardson and Mr. Witmer. 1915 MI Univ. College Engin. Proc. Short Course Highway Engin. 160 MD, There is one way to control it [=traffic speed] (if all other fail), and that is by building slight breakers across the road, which will either stop it or throw the speed maniac out of his car. [DARE Ed: This quot may belong rather at speed breaker n, but region and date suggest that it belongs here.] 1920 New Oxford Item (PA) 18 Nov 1/4, Mr. Feiser jumped upon the running board to ride along. In passing over a breaker in the road the door to which he was holding sprang open and Mr. Feiser was thrown to the hard roadbed. 1932 Frederick Post (MD) 16 Nov 1/1, The truck suddenly went over a breaker and the load it carried caused the machine to sway. 1940 Eve. Sun (Hanover PA) 21 Nov 9/2, Mr. and Mrs. Stanley Kretzinger, Hagerstown, had entered suit against the borough as the result of injuries alleged to have been suffered by the wife when a car operated by the husband went over a “breaker” on Baer avenue. 1968 DARE (Qu. N30, . . A sudden short dip in the road) Inf MD31, Breaker; PA134, Breaker, gutter. 1974 Bedford Co. Inquirer (PA) 20 Dec 1/2, Mary Pearl Hunt well remembers the days in early Friends Cove when she and sister Dorothy curled down in the straw beneath two warm buffalo robes in the family sleigh to go visiting on Christmas Day, and the frequent stops to rest the team behind breakers on ridges like that at Lutzville.
3 also attrib; In coal mining: a tower in which anthracite is broken up and the slate removed.
5 A breakwater. Cf breakwall n