noun, noun or participle which takes 'suru', transitive verb
guessing game
A casual game where participants try to guess something, often played by children. The っこ suffix adds a sense of friendly competition or mutual action.
子供たちは箱の中身を当てっこして遊んだ。
The children played a guessing game about what was inside the box.
誰が一番早く答
Let's have a guessing game to see who can answer first.