Seasonal hunger means the hunger which comes in the season,i.e., you will not have any work or occupation to do in certain months in an year.
This is known as the seasonal hunger.
For example, the small farmers will work in their lands.
They will seed, plough, etc... in their land.
Then, after harvest, they will do not have any work, i.e., after the six months of harvest, there will be no work for them. They have to wait for the next season.
But, if they don't have any work, there will be income, and they will be suffered.
Such a condition will be termed as the seasonal hunger.
Hope this will help you.