Neat and smart in appearance, or a type of evergreen tree; can also mean to make something look tidier and more attractive.
From German 'Sprucebark' (Prussia bark), originally referring to leather from Prussia. Later applied to the tree that grew there. The adjective sense developed from the fine appearance of Prussian goods in the 16th century.
Prussia was so famous for quality leather and fine goods that 'Prussian' became shortened to 'spruce' and eventually meant 'fashionable and neat'—basically medieval marketing! The same word for a tree and for being well-dressed shows how one product defined a whole style.
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