lighten

1 of 2

verb (1)

light·​en ˈlī-tᵊn How to pronounce lighten (audio)
lightened; lightening ˈlīt-niŋ How to pronounce lighten (audio)
ˈlī-tᵊn-iŋ

transitive verb

1
: to make light or clear : illuminate
2
archaic : enlighten
3
: to make (something, such as a color) lighter

intransitive verb

1
a
archaic : to shine brightly
b
: to grow lighter : brighten
2
: to give out flashes of lightning

lighten

2 of 2

verb (2)

lightened; lightening ˈlīt-niŋ How to pronounce lighten (audio)
ˈlī-tᵊn-iŋ

transitive verb

1
a
: to relieve of a burden in whole or in part
the news lightened his mind
b
: to reduce in weight or quantity : lessen
c
: to make less wearisome : alleviate
lighten our sorrow
2

intransitive verb

1
: to become lighter or less burdensome
2
: to become more cheerful
Choose the Right Synonym for lighten

relieve, alleviate, lighten, assuage, mitigate, allay mean to make something less grievous.

relieve implies a lifting of enough of a burden to make it tolerable.

took an aspirin to relieve the pain

alleviate implies temporary or partial lessening of pain or distress.

the lotion alleviated the itching

lighten implies reducing a burdensome or depressing weight.

good news would lighten our worries

assuage implies softening or sweetening what is harsh or disagreeable.

ocean breezes assuaged the intense heat

mitigate suggests a moderating or countering of the effect of something violent or painful.

the need to mitigate barbaric laws

allay implies an effective calming or soothing of fears or alarms.

allayed their fears

Examples of lighten in a Sentence

Verb (1) the room was gradually lightened by the rising sun Verb (2) the patient lightened when he heard the disease responds well to treatment
Recent Examples on the Web
Examples are automatically compiled from online sources to show current usage. Read More Opinions expressed in the examples do not represent those of Merriam-Webster or its editors. Send us feedback.
Verb
Further experiments showed that blue LED treatments safely lightened similar squalene stains on silk and polyester, while also mitigating stains from common stain-causing compounds like oleic acid, tomato juice, and orange juice. Andrew Paul, Popular Science, 3 Sep. 2025 Those who frequent salons know that lightening one's hair is much longer, more delicate process than going in the other direction, and Stone has slowly been making her way back to auburn since switching to a dark brunette shade in the summer of 2024. Emily Tannenbaum, Glamour, 30 Aug. 2025 The propeller steering mechanism also simplifies and lightens the mounting hardware, adding to total weight savings, and allows multiple outboards to be mounted closer together. New Atlas, 29 Aug. 2025 For their final Miami activity, everyone goes to the beach to sit under umbrellas, get a tutorial from Aaron about how to lighten your hair with lemon juice, and watch Kaylor and Aaron go at it yet again. Olivia Crandall, Vulture, 29 Aug. 2025 See All Example Sentences for lighten

Word History

Etymology

Verb (1)

Middle English lightenen, from light

First Known Use

Verb (1)

14th century, in the meaning defined at transitive sense 1

Verb (2)

14th century, in the meaning defined at transitive sense 1a

Time Traveler
The first known use of lighten was in the 14th century

Cite this Entry

“Lighten.” Merriam-Webster.com Dictionary, Merriam-Webster, https://www.merriam-webster.com/dictionary/lighten. Accessed 8 Sep. 2025.

Kids Definition

lighten

1 of 2 verb
light·​en ˈlīt-ᵊn How to pronounce lighten (audio)
lightened; lightening ˈlīt-niŋ How to pronounce lighten (audio)
-ᵊn-iŋ
1
: to make or become light, lighter, or clear : brighten
2
: to give out flashes of lightning
lightener
ˈlīt-nər How to pronounce lighten (audio)
-ᵊn-ər
noun

lighten

2 of 2 verb
lightened; lightening ˈlīt-niŋ How to pronounce lighten (audio)
-ᵊn-iŋ
: to make or become less heavy or less difficult
lighten a load
lightened her duties
lightener
ˈlīt-nər How to pronounce lighten (audio)
-ᵊn-ər
noun

More from Merriam-Webster on lighten

Last Updated: - Updated example sentences
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