An article by Jan Griffiths in the Guardian on 26 September began by describing a silent spring without birdsong: “No chittering, no fluting, no chissicking ...”. Chittering I knew to mean a series of short, sharp sounds, a cross between twittering and chattering (chitter is actually a variation of chatter). But chissicking was new.
Harold Orton’s Survey of English Dialects has an entry for it as an Essex term for clearing one’s throat with a forced cough. It has been applied to the sound the woodcock makes, which is fair enough, since one author described it as a series of grunts followed by a sneeze. As it has been, the croak of a jackdaw may also, with some poetic licence be, called chissicking in the Essex sense. It’s a stretch to use it of starlings, as the Yorkshireman Richard Kearton did in Nature’s Carol Singers in 1906; he wrote of the birds “sitting in one black mass on every available branch and bough, producing an indescribable din by all chissicking and chattering to each other at the same time”. Starlings make lots of noises and certainly chatter (or chitter) inordinately. But throat-clearing noises? Surely not?
British readers knew it as an attempt to render the sounds of common birds (song may be too grand a term). Gill Dunn wrote: “Like many birders, if I heard chissicking I would immediately look for a pied wagtail. Hearing one pass overhead has often been called a Chiswick Flyover.” (The Chiswick Flyover is an elevated motorway in west London; we Brits pronounce Chiswick as chizzick.) Also from the UK, Neil Paknadel found the noun as a description of the sound made by the house sparrow, in The Birds of Britain and Europe by Heinzel, Fitter & Parslow (1972): “Vocabulary of chirps and cheeps, with a double ‘chissick’, sometimes strung together as a rudimentary song.”
All this suggests that the source of the word in the sense that Jan Griffiths was using it isn’t the Essex term but an attempt to imitate the sounds made by various birds.