A gerbil is a small mammal of the order Rodentia. Once known simply as  desert rats , the gerbil subfamily includes about 110 species of African, Indian, and Asian rodents, including sand rats and jirds, all of which are adapted to arid habitats.
Vermouth, quinquina and americano are also fortified wines. Fortified means the alcohol percentage of the wine has been raised through the addition of spirits (a fairly neutral grape brandy is ideal in most cases). Almost all these wines have a white wine or mistelle base.
When mixing a single drink, one part is usually the equivalent of 1 ounce. A classic vodka martini, for example, uses six parts of vodka and one part of dry vermouth, which is the equivalent of 6 ounces of vodka and 1 ounce of dry vermouth. To make a pitcher of martinis using 1/2-cup measurements as the parts instead of ounces is the same as mixing 3 cups of vodka and 1/2 cup of dry vermouth.