Synonyms for Fateful (same or very similar meaning)
WordNet sense 1 (ominously prophetic):
foreboding, portentous
WordNet sense 2 (foretelling events as if by supernatural intervention):
prophetic, prophetical
WordNet sense 3 ((of events) having extremely unfortunate or dire consequences; bringing ruin):
black, calamitous, disastrous, fatal
WordNet sense 4 (not favored by fortune; marked or accompanied by or resulting in ill fortune):
unfortunate
WordNet sense 5 (determining or having the power to determine an outcome):
decisive
WordNet sense 6 (incapable of being avoided or prevented):
inevitable
From the ODE community, based on WordNet
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