Etymology Unknown. Perhaps a blend of squash + quell + quench. Compare also English squolsh, English squoosh.
1
US To halt, stop, eliminate, stamp out, or put down, often suddenly or by force.
Even the king's announcement could not squelch the rumors.
Oh 'twas your luck and mine to be squelched.c. 1615–1616, Thomas Middleton, John Fletcher, “The Nice Valour, or, The Passionate Mad-man”, in Comedies and Tragedies […], London: […] Humphrey Robinson, […], and for Humphrey Moseley […], published 1647, →OCLC, Act V, scene i:
3 more examples
If you deceive us you will be squelched.1858–1865, Thomas Carlyle, History of Friedrich II. of Prussia, Called Frederick the Great, volume (please specify |volume=I to VI), London: Chapman and Hall, […], →OCLC:
The party’s dominant right wing squelched not only Sherman’s hopes for an early convention, but may have also put the MLA out of contention for the leadership.1982 December 11, Frances Russell, “Economic performance buoys Pawley’s position”, in The Vancouver Sun (The Weekend Sun), Vancouver, BC, page A6:
We believe that Facebook is using privacy as a pretext to squelch research that it considers inconvenient.2021 August 10, Laura Edelson, Damon McCoy, “We Research Misinformation on Facebook. It Just Disabled Our Accounts.”, in The New York Times, →ISSN:
2
Broadcasting, Electrical engineering, Engineering, Media, Natural sciences, Physical sciences, Radio, Radio technology To suppress the unwanted hiss or static between received transmissions by adjusting a threshold level for signal strength.
3
UK To make a sucking, splashing noise as when walking on muddy ground.
The mud squelched underfoot; it had been raining all night.
[After they both fell into the lake.] Reaching the mainland some moments later and squelching back to the house, accompanied by Bobbie, like a couple of Napoleons squelching back from Moscow, [...]1960, P[elham] G[renville] Wodehouse, chapter XVI, in Jeeves in the Offing, London: Herbert Jenkins, →OCLC:
4
UK To walk or step through a substance such as mud.
The mud was thick and sticky underfoot, but we squelched through it nonetheless.
Entertainment, Lifestyle, Music A kind of electronic beat or sound mainly used in acid house and related music genres.
Through a process of experimentation the 'acid squelch' sound came forth, which was recorded and passed on to DJ Ron Hardy to play at his Warehouse club.1998, Colin Larkin, The Virgin Encyclopedia of Dance Music, page 91: