dinner lady 
noun British informal
A woman who serves meals to children in a school.My wife also served as a dinner lady at the school....
- I remember on June 6, 1944, just before I left school at 14 years old, we went into school dinner and our dinner lady told us that our boys had invaded France.
- A local dinner lady has challenged a group which claims school meals are ‘muck off a truck’ to try her food.