noun, feminine/kwaɾˈtiʝa/plural: cuartillas
A5 (a paper size); cuartilla, half-cuarto, quarter-fanega (a traditional unit of dry measure, equivalent to about 13.9 L); cuartilla, quarter-real (a former Mexican coin); pastern (of a horse)
From cuarto and cuarta (“fourth, quarter”) + -illa (“-elle: forming diminutives”), from Latin quartus (“fourth”). Doublet of cuartillo.