In a recipe, a "dash" indicates about 1/16 of a teaspoon. Many old recipes have non-standard measurements that were understood during the original era but are sometimes confusing to modern cooks.
For example, a "pinch" means about the same amount as a "dash." A "smidgen" is even less, perhaps around 1/32 of a teaspoon. If a recipe calls for "a few grains" or a "tad" of a substance, a cook should add no more than 1/8 of a teaspoon. A "handful" equals about 1 ounce of an ingredient. When a recipe requires a "saucer" of an ingredient, about 9 ounces are needed. Eggs are generally purchased by the dozen, and a recipe that requires a pound of eggs uses a dozen medium-sized eggs.