Synonyms for Sorrow (same or very similar meaning)
WordNet sense 1 (the state of being sad):
sadness, sorrowfulness
WordNet sense 2 (sadness associated with some wrong done or some disappointment):
regret, rue, ruefulness
WordNet sense 3 (something that causes great unhappiness):
grief
WordNet sense 4 (feel grief; eat one's heart out):
grieve
From the ODE community, based on WordNet
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