Go
The Game Of Go
noun
The kanji and the word are exactly the same. That means they share meanings as well, so this is Go, as in the game of Go.
碁 is the classic East Asian game of strategy played with black and white stones on a large grid board. It can be used on its own, but you'll also often see it in compounds such as 碁石 (ごいし) or 碁会所 (ごかいしょ).
The reading is the same as the one you learned with the kanji.
彼は子どものころから碁を打っています。
He has been playing Go since childhood.
年寄りたちと碁は打ちたくないんだよね。
I just don't want to play Go with old people.
父は碁で負けたことをずっと根に持っているんだよ。
My dad still holds a grudge about losing in Go.
碁石を盤にパチっと打ちつけるイメージから、「碁を打つ」という言葉が使われます。
The expression "碁を打つ" comes from the image of lightly tapping a Go stone onto the board with a crisp sound.