smoke

The word 'smoke' descends from Old English 'smoca' (smoke, fumes), related to the verb 'smēocan' (to‌​‍​‌​‌​‍​‌​‍​‌​‍​‍​‌​‌​‍​‌​‌​‍​‍​‌​‍​‌​‌​‍​‌​‍​‌​‍​‌​‌​‍​‍​‍​‌ emit smoke, to fumigate), from Proto-Germanic *smukō- or the verb *smeukanan (to smoke), from PIE *smeugʰ- (to smoke, to smolder). The word has been stable in meaning across its entire history — smoke has always meant the visible product of combustion.

The Germanic cognates include Middle Low German 'smōk,' Middle Dutch 'smooc,' and dialectal German 'Schmauch' (dense smoke, fumes). The verb 'to smoke' — both in the sense of 'to emit smoke' and 'to inhale tobacco smoke' — derives from the same Old English root. The tobacco sense dates from the late 16th century, shortly after the introduction of tobacco to Europe from the Americas.

Outside Germanic, the PIE root *smeugʰ- appears in Greek 'smýkhein' (σμύχειν, to smolder, to burn slowly) and possibly in Lithuanian 'smaugti' (to choke, to strangle), which captures the suffocating quality of smoke rather than its visible quality. If the Lithuanian connection holds, the PIE root encompassed both the visual phenomenon (the visible cloud) and its physiological effect (the choking of the lungs) — a dual nature that speakers have always recognized.

The word 'smolder' (to burn slowly without flame, producing smoke) may be related, though its exact etymology is debated. Middle English 'smolderen' might represent a frequentative or intensive form based on the same root — to smolder is to smoke continuously and quietly. The semantic link is clear even if the phonological derivation is uncertain.

'Smokescreen,' in its literal military sense (a cloud of smoke deployed to conceal troop movements), dates from World War I. The figurative sense (any action or statement designed to conceal true intentions) followed almost immediately — by the 1920s, 'smokescreen' was standard political vocabulary.

The portmanteau 'smog' was coined in 1905 by Dr. Harold Antoine Des Voeux, a member of the Coal Smoke Abatement Society, to describe the mixture of smoke and fog that blanketed London and other industrial cities. The word blends 'smoke' + 'fog,' both Germanic words, making 'smog' a rare modern technical term that owes nothing to Latin or Greek. The Great Smog of London in December 1952, which killed an estimated 4,000–12,000 people, led directly to the Clean Air Act of 1956.

The phrase 'where there's smoke, there's fire' — meaning that evidence of a problem indicates a real underlying issue — dates from the 16th century and reflects the unbreakable physical relationship between combustion and its visible byproduct. 'To go up in smoke' (to be destroyed, to vanish) and 'smoke and mirrors' (deception, illusion) both exploit the ephemeral, insubstantial nature of smoke — it is visible but untouchable, present but intangible, a substance that exists only in the act of disappearing.