Dozen usually means twelve things or items together. It is a common way to count many objects as a group of twelve.
I bought a dozen eggs today.
She needs a dozen chairs for the party.
Dozen can mean many things but not exactly twelve. It shows a large number of items or people without counting each one.
Dozens of people came to the event.
She has dozens of books on her shelf.
In shopping or business, dozen is a fixed unit meaning twelve items sold or counted together. It helps in pricing and selling products easily.
The store sells pencils by the dozen.
You can buy cans of soda by the dozen.
Dozens can be used in everyday speech to mean many things or people, usually more than ten but not exact. It's an informal way to say 'lots'.
Dozens of stars shine in the sky.
There were dozens of cars on the road.
Dozen can be used figuratively to highlight a large number of occurrences, errors, or ideas, giving stronger emphasis than just 'a lot'.
He made dozens of mistakes during the test.
They gave dozens of reasons for the delay.
In cooking and baking, dozen is a useful measure meaning twelve items like eggs, cookies, or rolls, often mentioned in recipes or shopping lists.
The recipe calls for one dozen cookies.
We bought a dozen rolls for breakfast.
In sports or games, a dozen can be used to count or highlight twelve points, goals, or other scoring units a player or team gets.
He scored a dozen points in the game.
They needed a dozen hits to win.
