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Webster 1913 Edition

(skwīr-ēn′)

Noun.

One who is half squire and half farmer; – used humorously.

[Eng.]

C. Kingsley.

squireen ‎(plural squireens)

A person who is half squire, half farmer.
"About 1730 the poet and squireen Huw Hughes wrote to the great scholar Lewis Morris that all the defenders of the old language had gone to sleep." - Prys Morgan, in "The Invention of Tradition"
Used by Graham in Poldark Novels freighted with contempt implying the objects of contempt were self-promoted or "jumped up".