Kalmar "fluidram" raka'a ce ta ma'auni don ƙara, kuma tana daidai da kusan milliliters 3.7 ko 1/8 na oza mai ruwa. An fi amfani dashi a cikin kantin magani don auna ruwa, kamar magani ko wasu mafita. An samo kalmar daga kalmar Latin "drachma," wanda ke nufin raka'a na nauyi ko girma.
