What does foggy mean?
Foggy is an adjective with two principal uses: it describes physical conditions thick with fog, where visibility is reduced and the landscape appears blurred or veiled, and it figuratively describes mental haziness, when thinking or memory feels slow and indistinct. The word derives from 'fog', itself a term with an interesting history in English weather vocabulary. Foggy mornings, foggy roads, and foggy harbours are familiar settings in literature and daily speech alike, lending the word strong associations with atmosphere, mystery, and caution — drivers are warned on foggy nights, and writers often use fog to evoke uncertainty. The figurative sense has grown especially relevant in modern life, where phrases like 'brain fog' make foggy a natural way to describe tiredness, illness, or information overload. Simple, evocative, and versatile, foggy bridges the literal and metaphorical with ease.
adjectiveFoggy describes conditions filled or obscured by fog, or, in a figurative sense, a mind or memory that is hazy, unclear, or unable to think distinctly.
- (Of the weather or air) filled with or obscured by fog; having low visibility.
- (Of the mind, memory, or thinking) cloudy, hazy, or lacking clarity — often used informally as 'brain fog'.
- (Of glass, windows, or lenses) covered or blurred by condensation or mist.
"The harbour was so foggy that the ferry's horn echoed through the mist for nearly an hour before docking."
"The drive across the moors was slow and tense, the road barely visible through the foggy dawn."
"She shook her head, trying to clear her foggy thoughts after another sleepless night."
London's Great Smog of 1952 was so foggy that visibility dropped to mere feet — and it directly inspired modern clean-air laws.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of foggy
Foggy comes from 'fog', the meteorological term for condensed water vapour hanging in the air near the ground. The word 'fog' entered general English use around the early modern period, though its exact origin remains debated — some scholars link it to Old Norse words for spray or long grass, while others point to earlier meanings related to damp, rank vegetation. From this root came derivatives including 'befog' and 'foghorn', and the adjective foggy developed to describe anything obscured or characterised by such vapour, later extending figuratively to states of mental confusion.
Related word forms
How foggy is actually used
Foggy is neutral in register and works in both everyday conversation and descriptive writing. Its figurative use for mental cloudiness ('my brain feels foggy') is common and informal but widely understood. In British English, the vowel is typically pronounced /ɒ/, while American English favours /ɑː/.
Easily confused with foggy
"Groggy" refers to dizziness or weakness, often after illness or sleep, while "foggy" refers to haze in the air or mental cloudiness.