cracker (n.1)

15世纪中叶, “硬晶片”, 但具体应用到薄脆饼干是由1739年; 字面意思是“那裂开或破碎,” 代理名词从 crack (v.). 意为“用于压碎或裂开的工具”, 来自1630年代.

Coal-cracker 来自1853年的人, 1857年的机器, 把开采的煤打碎. Cracker-barrel (1861年) “桶里装满苏打饼干出售” 是乡村老店的常见特征, 以至于到1905年, 这个短语被用作形容词, “体现了下乡的方式和观点”.

cracker (n.2)

美国南部对“贫穷的白人垃圾” 的贬义词(1766年), 可能是来自 crack (v.) 的代理名词, 意思是“吹嘘” (如 not what it's cracked up to be). Cracker “吹嘘者, 炫耀者” 从16世纪就有证据; 也见 crack (n.). 比较拉丁文 crepare “拨浪鼓, 噼里啪啦, 吱吱作响”, 其次要的形象意义是“夸耀, 喋喋不休, 小题大做”.

I should explain to your Lordship what is meant by crackers; a name they have got from being great boasters; they are a lawless set of rascalls on the frontiers of Virginia, Maryland, the Carolinas and Georgia, who often change their places of abode. [letter from colonial officer Gavin Cochrane to the Earl of Dartmouth, June 27, 1766]

但DARE比较 corn-cracker “Kentuckian”, 也是“佐治亚州和北卡罗来纳州的贫穷, 低级的白人农民” (1835年, 美国中西部口语).

该词到1808年特别用于乔治亚人, 虽然经常扩展到佛罗里达州北部的居民. 19世纪中叶使用的另一个名称是 sand-hiller “佐治亚州或南卡罗来纳州的贫穷白人”.

Not very essentially different is the condition of a class of people living in the pine-barrens nearest the coast [of South Carolina], as described to me by a rice-planter. They seldom have any meat, he said, except they steal hogs, which belong to the planters, or their negroes, and their chief diet is rice and milk. “They are small, gaunt, and cadaverous, and their skin is just the color of the sand-hills they live on. They are quite incapable of applying themselves steadily to any labor, and their habits are very much like those of the old Indians.” [Frederick Law Olmsted, “A Journey in the Seaboard Slave States,” 1856]

Definitions of cracker

cracker (n.)
a thin crisp wafer made of flour and water with or without leavening and shortening; unsweetened or semisweet;
cracker (n.)
a poor White person in the southern United States;
Synonyms: redneck
cracker (n.)
a programmer who cracks (gains unauthorized access to) computers, typically to do malicious things;
crackers are often mistakenly called hackers
cracker (n.)
firework consisting of a small explosive charge and fuse in a heavy paper casing;
Synonyms: firecracker / banger
cracker (n.)
a party favor consisting of a paper roll (usually containing candy or a small favor) that pops when pulled at both ends;
Synonyms: snapper / cracker bonbon