Pluckily is from plucky (from pluck 'courage, spirit', a figurative use of pluck 'the heart, liver, and lungs of a slaughtered animal') + -ly. Important recorded forms include pluccian (Old English). Morphologically, the word preserves a built structure whose named elements carry the historical sense into English. The modern sense remains close to that composition, with the parts narrowing into a single lexical item. In current use it covers in a brave and spirited manner. The wider family includes related words such as pluck, plucky, and pluckiness.