I’m sure I don’t need to remind you of the two main meanings of ‘plonk’: 1) the verb ‘to plonk’ (often followed by ‘on to’), meaning to place energetically, as in ‘she plonked the bottle on to the table’. In other words, it is an onomatopoeic verb; and 2) a noun indicating ‘a cheap and usually inferior wine’.

This last usage started out as ‘plink-plonk’, first recorded in 1930 but in all likelihood originally coined by British and Australian soldiers during World War I when garbling the French words ‘vin blanc’, i.e. enunciating the ‘n’ in both ‘vin’ and ‘blanc’, as well as the ‘c’ in ‘blanc’. ‘Plink-plonk’ was soon shortened to ‘plonk’. This process involving a change in the pronunciation of words borrowed by one language from another in order to conform with the sounds used by the borrowing language is known as the rule of Hobson-Jobson. What is, or who were, Hobson-Jobson, you may well ask. A firm of solicitors maybe? No, Hobson-Jobson is the short title of a book published in 1886 by Henry Yule and Arthur C. Burnell, Hobson-Jobson: A Glossary of Colloquial Anglo-Indian Words and Phrases, and of Kindred Terms, Etymological, Historical, Geographical and Discursive. Well-known examples of this process include kedgeree (khichri), mulligatawny (milagu-tannir) and curry (kari). The authors decided to entitle their book Hobson-Jobson because in Anglo-Indian English, the term Hobson-Jobson referred in particular to the Mourning of Muharram. The words ‘Yā Hasan! Yā Hosain!’, which were chanted by Shia Muslims during the procession of the Muharram, were then turned by British soldiers into Hosseen Gosseen, Hossy Gossy and finally Hobson-Jobson.

But we have not quite finished with the word ‘plonk’. In 1970s British police slang, a ‘plonk’ was a female police officer. It no doubt had derogatory connotations, because the word could also mean ‘penis’. ‘Plonker’ (or ‘plonka’), a word coined in the early 1980s and meaning an ‘idiot’ or a ‘wally’ may derive from that sense.

As for the modern sense of ‘plinkety-plonk’, it would seem to be an onomatopoeic adjective, applicable to anything from the strumming of a guitar, a cat on the keyboard, or the music of Alban Berg.