A very common expression of contempt is git. Roddy Doyle used it in one of his novels. I wouldn't think his namesake Ruth Doyle from Artane would use it but at least she is interested enough to ask where it comes from. It means, of course, offspring, progeny, especially a person born out of wedlock; an unruly brat; an eejit. It is a variant of get and this is from the Old Norse geta, to beget.
The old Scottish poets were fond of the word as a term of opprobrium. They used to pull no punches in having a go in print at other practitioners, and Cranstoun's edition of the Satirical Poems (1567) contains the marvellous opener, "Blasphemus baird and beggeris gitt".
A Carlow reader, Mary Gladney, wrote to ask about the word gudget, a glutton. I've heard this word all over the south-east. Recently a Waterford farmer complained to me that a gudget he had working for him would eat a horse for his breakfast. Moylan has the word in his Kilkenny dictionary: he quotes an informant who explained the word as "a little selfish lump of a person, especially in respect of food".
Gudget is found in Scotland and in Northampton. It is related to the verb gudge, to stuff, to eat ravenously, but the original meaning seems to be a camp follower, hence a menial or low type.
The word's origin is the French gouget. Andrew Duncan's Appendix Etymologiae of 1595 defines the word as a burden-bearer.
Flibbertigibbet, noun, is common enough where I grew up. I had always thought the word to mean a ragged person, a tatterdemalion. A letter from John Power of Waterford confirmed my own definition, but when I went searching for the origin of the word I found that Oxford says that it is an onomatopoeic representation of "chatter", and holds that the earliest form of the word, flibbergib, is probably the original. Flibbergib also meant a flighty or frivolous woman.
Oxford quotes one of Latimer's sermons before Edward V11 in 1549: "These flybbergybers an other days shall come and clawe you by the backe." In 1611 Cotgrave's dictionary defines the French coquette as "a pratling, a titifill, a flebergebit".
I looked up Wright's great dialect dictionary and found that our south-eastern flibbertigibbet, a ragamuffin, is found only in Warwickshire, Berkshire and Somerset across the water.
Where did we get our meaning, I wonder? Probably from the ragged, talkative urchin of Scott's Kenilworth, "Dickie Sludge, or Flibbertigibbet," it has been suggested.