To my mind, one of the nastiest faults you'll find in a child's pony is a propensity to cave, that is, to stretch his neck towards the ground and to bring it back up again suddenly, an action that can break a nose or knock a child unconscious. Some years back, I smiled when I saw the greatest jockey of them all deal with a caving horse down at the stalls on the Curragh; he gave the animal a smart whack of his stick between the ears and the caper suddenly ended. Not a practice I approve of, of course. But it works.
This verb cave, as I know it, is found in Ulster, and the Travellers of Leinster are also familiar with it. Macafee's Concise Ulster Dictionary adds: "of cattle, to push with the horns"; and the English Dialect Dictionary adds to the equine head-butting the following: "to paw the ground, rear, plunge, as a horse." These additional meanings make sense etymologically, even if they are unknown to the horse-copers I know; the verb is, in all probability, from Old Norse kaf, a plunge. Jessica Davies, from Cardiff, on holiday in Sallins, Col Kildare, wrote to ask about the word.
John Sweeney from Sutton asks what the origin of the word luchter is, as in "a luchter of hay of oats", a small quantity, a handful. This word is confined to Ulster; indeed it may be confined to Donegal. It is found in Donegal Irish as luchtar, which Dinneen defines as "a handful, a reaper's handful of corn." This was its original meaning in Scots. But we may look further afield for its origin: the Old Norse lagthr, which to the Vikings meant a handful of wool.
"She shut up like a clam": Mrs J. Considine from Limerick asks if the clam in question is the edible bivalve mollusc. She has always thought so until she heard a vet refer to an animal trap as a clam.
I'm not sure what the answer is. Simmons's Donegal glossary, written in 1890, has clam, a vice used by saddlers and shoemakers, but I've heard the word used for a rat trap in Waterford. As to origin, the word for both the mollusc and the trap come from the Old English clamm, a fetter, a constriction. But perhaps the importation of clam, a trap, is of more recent origin. Consider the Dutch klemme, a trap, a snare, mentioned in Hendrik Hexham's English-Dutch Dictionary of 1658.