Q From Mariah Blackhorse: A friend of mine took to contemplating the term cast dispersions and emailed me with his findings from searching the web. I always thought the term was cast aspersions but apparently both are, or have been, in usage. What are the origins and usage of these terms?
A Cast dispersions is an excellent example of a malapropism: using the wrong word through ignorance. The term is named after Mrs Malaprop, a comic character in Richard Brinsley Sheridan’s The Rivals, who constantly seeks to sound high-flown but fails catastrophically because she doesn’t know what the words she is using really mean. So she says of her daughter, “She should have a supercilious knowledge in accounts; and as she grew up, I would have her instructed in geometry, that she might know something of the contagious countries”.
In this case, aspersion is a relatively uncommon word and dispersion seems to fit better. Originally, aspersion was the action of sprinkling somebody with something, usually water — it was commonly used of one form of Christian baptism, for example. It comes from slightly older verbs asperse and asperge, both of which can be traced back to Latin aspergere, to sprinkle.
Around the middle of the seventeenth century, aspersion began to refer to the figurative idea that a person was sprinkling his neighbourhood with damaging imputations or false statements. Our modern idiom to cast aspersions seems to have been first used by Henry Fielding in his novel Tom Jones of 1749.