chalkboard
🇺🇸
/ˈtʃɔːkbɔːrd/
🇬🇧
/ˈtʃɔːkbɔːd/
A surface, usually black or dark green, that you can write on with chalk. It's often used in classrooms for teachers to write lessons.
The teacher wrote the math problem on the chalkboard for the class to see.