Mead is an alcoholic beverage made by fermenting honey that has been diluted by water. Mead was popularised in classical Greece and imperial Rome. It became the favourite drink of many European tribes after the fall of Rome.
Mead is a also favourite drink in the Wizarding world. In Harry Potter's third year, Rubeus Hagrid ordered five pints of mulled mead from Madam Rosmerta at the Three Broomsticks pub in Hogsmeade. Also, there was a rumour abound that Albus Dumbledore had ordered many barrels of Mead for the Yule Ball, but this was proven false. Harry first had
Ron Weasley, after getting poisened by drinking Horace Slughorn's Oak Matured Mead.
Mead in the summer of 1996 when Dumbledore arrived at 4 Privet Drive to explain Sirius Black's will to him. He remarked that though he had never had anything like it, he enjoyed it immensely. In Harry's sixth year at Hogwarts, Professor Horace Slughorn gave Ron Weasley a glass of oak-matured mead, after giving him the antidote to a Love Potion as a pick-me-up, unaware that the mead had been poisoned by Draco Malfoy, who had intended that the mead bottle reach Dumbledore. Only quick work by Harry Potter, who shoved a Bezoar down Ron's throat, saved his life.