"what is the meaning of this error?"
The .fig file format is really just a .mat that stores all of the objects in a figure. Most of the time this happens quite seamlessly, so the user never notices or cares how .fig files are saved. But .mat files are not all the same: in particular, the size of arrays that can be saved has increased significantly as MATLAB has developed. You can see these differences summarized here:
What appears to have happened is that whoever wrote the .fig saving code did not consider that someone might want to save a figure with such a huge amount of data, and the size is beyond the specification for the default .mat file version that the .fig saving code uses (here in bytes):
ans = 2147483648
ans = 3600000000
"how to avoid it?"
You might like to try using saveas, to see if it handles this better.
Otherwise I doubt that there is a simple solution, but I think you should definitely report this as a bug.