ominous - a. 불길한, 암운이 드리우는

• threatening
• warning
• baleful
• baneful
• dire
• inauspicious

• Those black clouds are a bit ominous.
• Consequently we busily create ominous circumstances which could make the 21st century even more dire than the 20th century.
• These ominous symptoms almost always mean a failed big end or main crankshaft bearing.