What is Cheese ?
Cheese is (noun) a solid food made from milk She ordered a cheese omelette and chips. At the end of the meal we’ll have biscuits and cheese. Can I have a pound of Cheshire cheese, please? ‘say cheese!’ used when asking people to smile when their photo is being taken (informal.) The photographer got us all in a line and then told us to ‘say cheese!’.
source: Easier English, Student Dictionary Upper Intermediate Level