Sufferance is a type of patience, especially the patience to endure pain and suffering.
When you suffer, you're in some type of pain, whether physical or emotional. Sufferance is a quality possessed by people who endure such pains patiently and without complaining. Someone who ensures a long and serious illness without complaining once has great sufferance. On the other hand, if you complain and whine about minor problems, that shows very little sufferance. This is a word for dealing with difficult situations well and even heroically.