When the Irish novelist Maria Edgeworth wrote a letter to a friend in April 1795, she commented on her recent reading, “It is a scarce and very ingenious book; some of the phraseology is so much out of the present fashion, that it would make you smile: such as the synonym for a little man, a Dandiprat.”
A dandiprat may be a dwarf or small boy but also sometimes an insignificant or contemptible person. She was somewhat premature in her claim that the word was unfashionable: it survives to be included in a few modern one-volume dictionaries because it turns up from time to time in historical or fantasy fiction. In evidence of this, I place this before you:
Who is so wise as to distinguish, with unerring precision, between a little man, a dwarf, a gnome, a midget, a shrimp, a runt, a pygmy, a Lilliputian, a chit, a fingerling, a pigwidgeon, a mite, a dandiprat, a micromorph, an homunculus, a dapperling, a small fry or someone with bad posture, weighted down with the cares of the world?
Forward the Mage, by Eric Flint and Richard Roach, 2002
though this perhaps proves no more than that Messrs Flint and Roach possess a thesaurus with historical pretensions.
Nobody has the slightest idea where the word comes from. It first appears in the language in the early sixteenth century in the sense of a small coin current at the time, curiously worth 1½ pence, but then quickly develops its other senses.