fastness

noun

ˈfas(t)-nəs How to pronounce fastness (audio)
Definition of fastnessnext
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

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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

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.
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
Recent Examples of Synonyms for fastness
  1. speed
  2. stronghold
  3. loyalty
  4. velocity
  5. fortress
  6. allegiance
  7. bastion
  8. dedication
Noun
  • The vessel had switched off its AIS transponder, a marine radio device that broadcasts a ship’s identity, speed, course and position.
    — David Goldman, CNN Money, 22 Aug. 2026
  • Torque arrives early, with the bulk of the 406 lb-ft available from low engine speeds, and the SQ5 builds speed with the sort of effortless authority that expensive German machinery has perfected.
    — New Atlas, New Atlas, 22 Aug. 2026
Definition of speed
Noun
  • The military has increasingly used airstrikes to counter opposition forces, including the armed People’s Defense Forces in Sagaing region, a stronghold of armed resistance.
    — Grant Peck, Los Angeles Times, 21 Aug. 2026
  • In the Almería suburb of La Cañada, one of Vox’s strongholds, those talking points are producing results.
    — Vasco Cotovio, CNN Money, 21 Aug. 2026
Definition of stronghold
Noun
  • As loyalty moves from a retention tactic to a growth engine, the redemption experience deserves the same design and measurement rigor CMOs already apply to the acquisition funnel.
    — Jeff Fromm, Forbes.com, 17 Aug. 2026
Definition of loyalty
Noun
  • Perhaps better health and shorter assignments will help Cabrera harness his high-end velocity and create greater separation between his fastball and a unique changeup.
    — Patrick Mooney, New York Times, 18 Aug. 2026
  • In our engineering teams, AI-first processes have increased velocity by handling boilerplate code, test generation and repetitive tasks, freeing developers to focus on architecture and problem-solving.
    — Khadim Batti, Forbes.com, 17 Aug. 2026
Definition of velocity
Noun
  • Another day trip option is the hilltop town of Erice, where there's a medieval fortress that's over 2,500 years old.
    — Megan Rose Murray, Condé Nast Traveler, 22 Aug. 2026
  • Cage plays Roy, a gifted con artist with obsessive-compulsive disorder whose tics, phobias and elaborate rituals have turned his immaculate home into a fortress against the world.
    — Los Angeles Times, Los Angeles Times, 20 Aug. 2026
Definition of fortress
Noun
  • The Argentine soccer star had not played at Subaru Park since 2023, and for many fans, the chance to see one of the sport's biggest names in person was worth temporarily setting aside their allegiance to the Philadelphia Union.
    — Eva Andersen, CBS News, 20 Aug. 2026
  • Investigators uncovered audio files of Bowie pledging her allegiance to ISIS, which the FBI identified from a reference to the current leader of the terrorist group.
    — Claire Carter, The Washington Examiner, 20 Aug. 2026
Definition of allegiance
Noun
  • The city’s standing as a bastion of British literature, theatre, and classical music means that festivals are also a major draw year-round, like February’s Bath BachFest and the Children’s Literature Festival in September.
    — Paul Jebara, Condé Nast Traveler, 18 Aug. 2026
  • President Emmanuel Macron and others who regard Europe as the last bastion of liberal Western values?
    — Ian Buruma, New Yorker, 10 Aug. 2026
Definition of bastion
Noun
  • Kids frolicked in the new Nikki Spoelstra Play Forest, one of the segment’s highlights, while a band played and vendors hawked food by South Miami City Hall as advocates and officials spoke at the dedication.
    — Andres Viglucci, Miami Herald, 17 Aug. 2026
  • Julius Murga has deep roots in Wrigleyville, but his dedication to Sports World Chicago is rivaled only by Ganal.
    — Noel Brennan, CBS News, 17 Aug. 2026
Definition of dedication

Browse Nearby Words

fasting
fastness
fasts
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Cite this Entry

“Fastness.” Merriam-Webster.com Thesaurus, Merriam-Webster, https://www.merriam-webster.com/thesaurus/fastness. Accessed 25 Aug. 2026.

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