The OED takes a more scientific approach, and the word fills several fascinating pages, which add Seventies black slang for wine, and the age- old pluck a rose - women's euphemism for urination when the privy was in the garden.Reuse content
CURIOUS, A word's diversity. Pluck is not only the entrails of an animal ground into sausages, but also an act of picking and feat of courage. One is restless until it's settled. Johnson posits a Saxon origin, ploccian, and notes, "It is very generally and licentiously used, particularly by Shakespeare." Courage - pluck up heart - is linked, but as for "the heart, liver and other lights of an animal", he moots Erse, plughk - "I know not whether derived from the English, rather than the English from the Erse."