1
as in speed
a high rate of movement or performance
the amazing fastness with which the boy took his shower had us wondering if he'd used any water
Synonyms & Similar Words
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Antonyms & Near Antonyms
2
as in stronghold
a structure or place from which one can resist attack
the guerillas retreated to their network of hidden fastnesses deep within the mountains
Synonyms & Similar Words
3
as in loyalty
adherence to something to which one is bound by a pledge or duty
his uncompromising fastness to the cause of freedom was beyond question
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Antonyms & Near Antonyms
Example Sentences
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Recent Examples of fastness
Editors and contributors compare dozens of sets and look for qualities such as softness, durability, breathability, color fastness, and how well the linens launder and withstand wear.
—
Yelena Moroz Alpert, Architectural Digest, 20 Jan. 2026
Li said the color builds the familiar ring-dye, white-core look designers expect, then fades predictably in laundry while maintaining high light fastness (Grade 4–5) and strong anti-yellowing.
—Angela Velasquez, Sourcing Journal, 11 Nov. 2025
Like the pressing, the hard work mentality and fastness of transition for example.
—Andy Jones, New York Times, 29 May 2025
The Neutral Ground had cowboys (or Cow Boys), Indians, cavalry attacks and rescues, and secret woodland fastnesses known only to the canniest frontiersman.
—Ian Frazier, The New Yorker, 15 July 2024
Yelena Moroz Alpert, Architectural Digest, 20 Jan. 2026
Li said the color builds the familiar ring-dye, white-core look designers expect, then fades predictably in laundry while maintaining high light fastness (Grade 4–5) and strong anti-yellowing.
—Angela Velasquez, Sourcing Journal, 11 Nov. 2025
Like the pressing, the hard work mentality and fastness of transition for example.
—Andy Jones, New York Times, 29 May 2025
The Neutral Ground had cowboys (or Cow Boys), Indians, cavalry attacks and rescues, and secret woodland fastnesses known only to the canniest frontiersman.
—Ian Frazier, The New Yorker, 15 July 2024
Recent Examples of Synonyms for fastness
Noun
-
In 1999, the Bridge Creek–Moore tornado struck the Oklahoma City metropolitan area, causing 41 deaths and nearly 600 injuries; the tornado’s top wind speed of 321 mph was the highest ever recorded on Earth.—
Chicago Tribune,
Chicago Tribune,
3 May 2026
-
The electrons that generate these bursts travel mainly along magnetic field lines at speeds approaching that of light, producing radio waves through a plasma emission process.—
Bojan Stojkovski,
Interesting Engineering,
3 May 2026
Noun
-
Goldbug ideology has received an intellectual sheen from places like George Mason University, a libertarian stronghold, where the Koch brothers have invested millions of dollars into research, including on gold and cryptocurrency.—
Jennifer Wilson,
New Yorker,
4 May 2026
-
Even if the White House is a stronghold, it is not meant to look like one.—
Neil Flanagan,
The Atlantic,
2 May 2026
Noun
-
The blockchain can include both upstream, meaning production and sourcing info, and downstream, meaning loyalty programs or insurance tied to an object, as well as repair and resale.—
Martino Carrera,
Footwear News,
6 May 2026
-
With 59% of younger viewers subscribing and unsubscribing from streamers to chase specific titles, what should streaming platforms do to adapt to this shift and foster long-term loyalty?—
Jennifer Maas,
Variety,
6 May 2026
Noun
-
His velocity, however, never quite returned.—
Abbey Mastracco,
New York Daily News,
7 May 2026
-
Thick electrode problem Electrochemical energy storage devices rely on a delicate balance between volume and velocity.—
Mrigakshi Dixit,
Interesting Engineering,
6 May 2026
Noun
-
The two stairwells are set within a 110-foot-wide core made of a concrete that’s stronger than any rock, creating a pressurized, smoke- and blast-resistant fortress.—
Michelle Sinclair Colman,
Curbed,
7 May 2026
-
The eccentric design of Olana was inspired by fortresses in Persia (where, curiously, Church hadn’t travelled), as well as Italian, East Indian, Gothic Revival, and French Second Empire architecture.—
Sebastian Smee,
New Yorker,
4 May 2026
Noun
-
My real allegiance, if burritos can inspire allegiance, is to the northern-Mexican style, made with a modest amount of filling and rolled into a consequentially narrower cylinder.—
Helen Rosner,
New Yorker,
3 May 2026
-
Naturalized citizens study American history, pass a civics test, swear allegiance to the United States, and accept the duties of membership in the political community.—
Matt Klink,
Oc Register,
1 May 2026
Noun
-
Climb the 900-odd steps (or cop out in a car) for a walk through its eight baroque bastions and some breathtaking views.—
Helen Brown,
TheWeek,
30 Apr. 2026
-
For more than a hundred years, the place has functioned as a crucial cultural bastion, hosting speakers like James Baldwin, Gwendolyn Brooks, and Allen Ginsberg.—
Brittany Allen,
Literary Hub,
21 Apr. 2026
Noun
-
Vogue's hosts asked her on the carpet, later commending her dedication to fashion, art and costume.—
Dalila Muata,
NBC news,
5 May 2026
-
Korean War fighter pilot and Medal of Honor recipient Royce Williams was honored May 1 at the Mount Soledad National Veterans Memorial in La Jolla with a formal ceremony and plaque dedication.—
Ashley Mackin Solomon,
San Diego Union-Tribune,
4 May 2026
Cite this Entry
“Fastness.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fastness. Accessed 8 May. 2026.
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