Webster's Revised Unabridged Dictionary · 1913

Ominous

Ominous , adjective

[Latin ominosus, from omen. See Omen.]

Of or pertaining to an omen or to omens; being or exhibiting an omen; significant; portentous; -- formerly used both in a favorable and unfavorable sense; now chiefly in the latter; foreboding or foreshowing evil; inauspicious; as, an ominous dread.
He had a good ominous name to have made a peace. — Bacon
In the heathen worship of God, a sacrifice without a heart was accounted ominous. — South