Indicating a large quantity or number; used as an adverb or noun (commonly written in kana 'たくさん').
今日はたくさん歩いたので疲れた。
I walked a lot today, so I'm tired.
たくさんの人が会場に集まった。
A large number of people gathered at the venue.
料理をたくさん作って友達を招いた。
I cooked a lot of food and invited friends.
たくさん練習すれば上手になる。
If you practice a lot, you'll improve.
Can also mean 'enough' or 'sufficient' in contexts like 'that's enough'.
もうたくさんです。これ以上は結構です。
That's enough. I don't need any more.
準備はたくさんあるから心配いらない。
We have plenty of preparations, so don't worry.
Used as a suffix after a noun in colloquial expressions (〜だくさん) to mean 'having many [X]'.
うちの近所には子だくさんの家が多い。
There are many households with lots of children in my neighborhood.