Bitter and rancorous feelings can twist even the prettiest countenance or heart into an ugly thing. Some are more predisposed than others to unkind thoughts and actions, while others are warped by circumstance and hardship. Whatever the cause, the results are as nasty as the names: harpy, shrew, witch, harridan.
When I think waspish, I immediately conjure two images: Lady Catherine de Bourgh and the Real Housewives of *insert city here.* No one likes to be the object of tittle-tattle or meanness, but many like to be in on the hearing and observation of it, and television has brought the most specious, intriguing, and sometimes salacious news and imaginings straight into our homes.
When a stroll through the interwebs turns up Jane Austen/RHOetc. mashup, well, heaven help us.
Slang term taken from the 1811 Dictionary of the Vulgar Tongue.