1.
having momentous consequences; of decisive importance
that fateful meeting of the U.N. when...it declared war on North Korea
2.
ominously prophetic
3.
(of events) having extremely unfortunate or dire consequences; bringing ruin
a fateful error
4.
controlled or decreed by fate; predetermined
The Pentagon, in Arlington, Virginia, has twice as many bathrooms as is
necessary. When it was built in the 1940s, the ste of Virginia still
had segregation laws requiring separate toilet facilities for blacks and
whites.