This phrase is applied to someone who is very strong and resilient in the face of hardship or pain. It originated in the USA in 1918; it has been used in British English since 1933.
the name of a decree issued in Nazi Germany in December 1941, under which individuals suspected of resistance or other underground activities were arrested and deported suddenly and without trace, frequently during the night—by extension: any situation, event, etc., characterised by mystery, obscurity or secrecy
USA—‘slobberknocker’ (1967): an American-Football player with a particularly aggressive style of play—from ‘slobber-knock’ (1964): of an American-Football player, to hit with extreme force—the image is of knocking the slobber out of somebody
USA, 1937—to have or cultivate a particular image or reputation which has no basis in reality; to engage in empty talk—now often thought of as referring to Texans, but originally attributed to Native Americans
USA, 1990—a persistent or indefatigable person or phenomenon—refers to ‘Energizer Bunny’, the name of a battery-operated toy rabbit represented as never running out of energy, featured from 1988 in a television advertising campaign for batteries
Since the mid-20th century, with reference to garden tea parties, the phrase ‘cucumber sandwiches on the lawn’ and its variants have been used to characterise traditional Englishness.
USA, 1907—refers to the supply of something to a place where it is not needed—in particular, ‘could sell sand in the Sahara’ is applied to an efficient salesman, and, by extension, to a persuasive person
USA, 1904—refers to the supply of something to a place where it is not needed—in particular, ‘could sell refrigerators to the Eskimos’ is applied to an efficient salesman, and, by extension, to a persuasive person
means that, if one is unaware of an unpleasant fact or situation, one cannot be troubled by it—coined by the English poet Thomas Gray in An Ode on a Distant Prospect of Eton College, first published in 1747