The number one million (1,000,000). Used to indicate amounts, counts, or quantities.
そのコンクールの賞金は１００万円だった。
The prize money for that contest was one million yen.
町の人口はおよそ１００万に達した。
The town's population reached about one million.
彼は雑誌で『１００万の読者を持つ』と紹介された。
He was introduced in the magazine as having one million readers.
Figuratively used to mean 'a great many' or 'countless' (as in 'a million ~').
彼女にはありがとうを言いたい人が百万いると言っていた。
She said there are a million people she wants to thank.
百万の星が夜空に瞬いているようだった。
It looked as if a million stars were twinkling in the night sky.