billow

1 of 2

noun

bil·​low ˈbi-(ˌ)lō 

1

: wave

especially : a great wave or surge of water

the rolling billows of the sea

2

: a rolling mass (as of flame or smoke) that resembles a high wave

Billows of smoke poured out of the building.

billows of fog

billowy

ˈbi-lə-wē 

adjective

billow

2 of 2

verb

billowed; billowing; billows

intransitive verb

1

: to rise or roll in waves or surges

the billowing sea

2

: to bulge or swell out (as through action of the wind)

billowing clouds

… the flags … billowed out in pride …

—G. B. Oxnam

transitive verb

: to cause to billow

a field of burning grass billowing thick black clouds of smoke into the sky

—Donald Windham

Synonyms

Noun

• surge
• swell
• wave

Verb

• bag
• balloon
• beetle
• belly
• bulge
• bunch
• jut
• overhang
• poke
• pooch [chiefly dialect]
• pouch
• pout
• project
• protrude
• stand out
• start
• stick out
• swell

Examples of billow in a Sentence

Noun

Billows of smoke poured out of the burning building.

the rolling billows of the sea

Verb

the curtains in the open windows billowed in the summer wind

Recent Examples on the Web

Noun

Smoke billows during Israeli shelling on the southern Lebanese village of Kfar Kila. —Andrea Mitchell, NBC News, 15 Oct. 2024

Just like the updrafts, this feeds the fire with fresh, oxygenated air; unlike updrafts, downbursts cause gusts that billow out away from the center of the fire, leading it to spread rapidly in multiple directions at once. —Ned Kleiner, Los Angeles Times, 22 Sep. 2024

Verb

Wildfire Smoke Is a ‘Public Health Threat’ That Can Have Lasting Impacts, Experts Say Images show firefighters battling intense flames, cars ablaze, and smoke billowing in the sky. —Maya Chung, TIME, 10 Dec. 2024

Smoke was billowing out but headed in the opposite direction of our flight pattern, giving us a clear view of the volcano. —Jaclyn Greenberg, WIRED, 5 Dec. 2024

Word History

Etymology

Noun and Verb

Old Norse bylgja; akin to Old High German balg bag — more at belly

First Known Use

Noun

1552, in the meaning defined at sense 1

Verb

1592, in the meaning defined at intransitive sense 1

Kids Definition

billow

1 of 2 noun

bil·​low ˈbil-ō 

1

: wave entry 2 sense 1

especially : a large wave

2

: a rolling mass like a high wave

billows of smoke

billow

2 of 2 verb

1

: to rise or roll in waves

the billowing ocean

2

: to bulge or swell out

sails billowing in the breeze