Related Clues:

• More than mist
• No mere mist
• Bewilderment
• With horn, invention of our R. Foulis
• Bane of sailors
• Brit's pea-souper
• Flying hazard
• Miasma
• Poor visibility
• Navigational hazard
• Mariner's hazard
• Visibility impairer
• Frequent London forecast
• It may come in a blanket
• Thick mist