Drinking is the act of ingesting water or other liquids into the body through the mouth. Water is required for many of life’s physiological processes. Both excessive and inadequate water intake are associated with health problems.
There’s a whole laundry list of “Drink like” and “Drunk as” similes. Those linking drinking with fish predominate with “Drunk as a lord” and “Drunk as owls” or “Boiled as owls” following close on the fishes’ fins. A nice twist by Mary Peterson Poole: “It’s all right to drink like a fish, if you drink what a fish drinks.”