muckraker (n.)youdaoicibaDictYouDict
c. 1600, "one who rakes muck," from muck (n.) + agent noun from rake (v.). Meaning "one who inquires into and publishes scandal and allegations of corruption among political and business leaders," popularized 1906 in speech by President Theodore Roosevelt, in reference to "man ... with a Muckrake in his hand" in Bunyan's "Pilgrim's Progress" (1684) who seeks worldly gain by raking filth.
The men with the muck-rakes are often indispensable to the well-being of society, but only if they know when to stop raking the muck. [T. Roosevelt, quoted in "Cincinnati Enquirer," April 15, 1906.]
Muckrake in sense "person who hunts scandal" is attested from 1872. To muckrake (v.) in the literal sense is from 1879; figuratively from 1910. Related: Muckraking.
whistle (n.)youdaoicibaDictYouDict
"tubular musical instrument sounded by blowing," Old English hwistle (see whistle (v.)). Meaning "sound formed by pursing the lips and blowing" is from mid-15c. To wet one's whistle "take a drink" (late 14c.) originally may have referred to pipes, or be an allusion to the throat as a sort of pipe. Phrase clean as a whistle is recorded from 1878. Railroad whistle-stop (at which trains stop only if the engineer hears a signal from the station) is recorded from 1934.
iffyoudaoicibaDictYouDict
"If and only if", 1950s: arbitrary extension of if.