dinner不仅仅指晚饭,还有正餐的说法.正餐可以在中午也可以在晚上.
Some people have dinner at noon, and other people have dinner in the evening.
有些人在中午吃正餐,还有些人在晚上吃正餐.
所以泛泛地说吃饭也是可以用havedinner的.