Dozen

1. A set of twelve. We cooked a dozen eggs for breakfast.
2. plural - Dozens - An indefinite, large number. I have dozens of errors to fix.
3. Eggs are traditionally sold by the dozen because the old imperial measurements such as inches, feet, pennies were all calculated by the dozen.The boxes made to carry these is part of the reason for this tradition to continue.
4. Additionally, you will notice many things are packed in dozens or factors/multiples of a dozen; such as donuts and soft drinks for example. You will also notice that many large volumes are sold in a "gross" which is a dozen dozens. The reason for this is that 12 allows for the most packaging options as it relates to dimensions; it can be factored as 12x1, 6x2, or 3x4. 10 on the other hand only has 10x1 and 5x2 which limits it's packaging options. This gets more important and complex when you are packaging in 3 dimensional boxes