Derived from an image of a cut bone, this kanji was used phonetically to mean seven.

Vocabulary

Vocabulary Reading Meaning
⭐ 七 しち／なな seven
⭐ 七つ ななつ seven things
⭐ 七五三 しちごさん the Shichi-Go-San festival

今年は娘の七五三だ。

Our daughter will be in the Shichi-Go-San festival this year.🔗
七日 なのか／なぬか seventh day of the month; seven days
七月 しちがつ July
四十七士 しじゅうしちし the 47 ronin
七福神 しちふくじん Seven Lucky Gods
七月目 ななつきめ the seventh month
七夕 たなばた Tanabata, the Star Festival (Wikipedia)