lagging

¹ American  

[lag-ing] / ˈlæg ɪŋ /

noun

1. the act of falling or staying behind.

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adjective

1. lingering; loitering; slow and dragging.

   lagging steps.

lagging ² American  

[lag-ing] / ˈlæg ɪŋ /

noun

1. the act of covering a boiler, oil tank, etc., with heat-insulating material.

2. the covering formed.

3. the material used.

4. a number of boards or the like joined together side by side to line an excavation.

5. Masonry. a number of lags, taken as a whole.

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lagging British  

/ ˈlæɡɪŋ /

noun

1. insulating material wrapped around pipes, boilers, etc, or laid in a roof loft, to prevent loss of heat

2. the act or process of applying lagging

3. a wooden frame used to support an arch during construction

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Other Word Forms

• laggingly
  adverb

Etymology

Origin of lagging¹

First recorded in 1590–1600; lag ¹ + -ing ¹, -ing ² ( def. )

Origin of lagging²

First recorded in 1850–55; lag ³ + -ing ¹

Example Sentences

As the race to advance AI heats up, some experts say that Apple has been lagging behind its rivals such as OpenAI’s ChatGPT and Google Gemini.

From Los Angeles Times • May 6, 2026

Analysts flagged the lagging performance of the international commercial business and noted that the stock’s sky-high valuation leaves little room for error.

From The Wall Street Journal • May 5, 2026

Sweden and Rwanda have both set ambitious targets of eliminating cervical cancer by 2027, separately launching accelerated vaccination and screening programmes, though both countries are lagging behind key milestones.

From BBC • May 1, 2026

Investors feared that Google Gemini was lagging behind competitors, but Gemini has grown to be the most downloaded AI app behind OpenAI’s ChatGPT, according to data from Sensor Tower.

From MarketWatch • Apr. 30, 2026

On September 1, 1949, Stalin taught America a hard lesson about the cost of lagging behind in the spy wars.

From "Spies: The Secret Showdown Between America and Russia" by Marc Favreau

Related Words

• underdeveloped