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Synonyms

lighten

1 American  
[lahyt-n] / ˈlaɪt n /

verb (used without object)

  1. to become lighter or less dark; brighten.

    The sky lightened after the storm.

  2. to brighten or light up, as the eyes or features.

    Her face lightened when she heard the good news.

  3. to flash as or like lightning (often used impersonally with it as subject).

    It thundered and lightened for hours.

  4. Archaic. to shine, gleam, or be bright.

    steel blades lightening in the sun.


verb (used with object)

  1. to give light to; illuminate.

    A full moon lightened the road.

  2. to brighten (the eyes, features, etc.).

    A large smile lightened his face.

  3. to make lighter or less dark.

    Add white to lighten the paint.

  4. Obsolete. enlighten.

  5. Obsolete. to flash or emit like lightning (usually followed by out, forth, ordown ).

    eyes that lightened forth implacable hatred.

lighten 2 American  
[lahyt-n] / ˈlaɪt n /

verb (used with object)

  1. to make lighter in weight.

    to lighten the load on a truck.

  2. to lessen the load of or upon.

    to lighten a cargo ship.

  3. to make less burdensome or oppressive; alleviate; mitigate.

    to lighten taxes;

    to lighten someone's cares.

    Synonyms:
    reduce, lessen, ease
    Antonyms:
    aggravate
  4. to cheer or gladden.

    Such news lightens my heart.


verb (used without object)

  1. to become less severe, stringent, or harsh; ease up.

    Border inspections have lightened recently.

  2. to become less heavy, cumbersome, burdensome, oppressive, etc..

    His worries seem to have lightened somewhat.

  3. to become less gloomy; perk up.

    People's spirits usually lighten when spring arrives.

lighten 1 British  
/ ˈlaɪtən /

verb

  1. to become or make light

  2. (intr) to shine; glow

  3. (intr) (of lightning) to flash

  4. (tr) an archaic word for enlighten

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

lighten 2 British  
/ ˈlaɪtən /

verb

  1. to make or become less heavy

  2. to make or become less burdensome or oppressive; mitigate

  3. to make or become more cheerful or lively

"Collins English Dictionary — Complete & Unabridged" 2012 Digital Edition © William Collins Sons & Co. Ltd. 1979, 1986 © HarperCollins Publishers 1998, 2000, 2003, 2005, 2006, 2007, 2009, 2012

Other Word Forms

Etymology

Origin of lighten1

First recorded in 1300–50; Middle English lightnen; see origin at light 1, -en 1

Origin of lighten2

First recorded in 1350–1400; Middle English lightnen; see origin at light 2, -en 1

Explanation

To lighten something is to make it brighter or shine a light on it. You can lighten your dark basement room with plenty of lamps and a coat of white paint. Besides "make lighter or illuminate," another meaning of lighten is "make lighter in weight." So you can lighten your load by taking all the heavy books out of your backpack. Figuratively, "to lighten" is to be more cheerful or relaxed, as in: "She decided to lighten the somber mood in the room by telling a few of her funniest knock-knock jokes."

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Example Sentences

Examples are provided to illustrate real-world usage of words in context. Any opinions expressed do not reflect the views of Dictionary.com.

See Examples For:

It wasn’t until after the release of that book, and then “Nickel Boys,” that Whitehead decided to lighten the mood by composing a crime novel set in New York City in the 1960s.

From Los Angeles Times Jul. 20, 2026

A greater national investment in mental health care might even lighten his own load, he conceded.

From Barron's Jul. 19, 2026

They may lighten the skull or influence voice resonance, and we can even use their size and variability for forensic identification.

From Science Daily Jul. 11, 2026

Flashes of publishing-world satire lighten the mood as the weekend celebration turns into a nightmare.

From The Wall Street Journal May 1, 2026

‘Yet maybe this will lighten your heart,’ said Galadriel; ‘for it was left in my care to be given to you, should you pass through this land.’

From "The Fellowship of the Ring" by J.R.R. Tolkien

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