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 Like the pressing, the hard work mentality and fastness of transition for example. — Andy Jones, New York Times, 29 May 2025 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 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 Beltline allows only Class 1 or 2 e-bikes and speeds of only up to 15 mph.
    — Doug Turnbull, AJC.com, 5 July 2026
  • Pfendler appears to have broken both the previous women's speed record as well as the men's speed record, according to records maintained by Ocean Rowing Society International, which adjudicates ocean-rowing achievements for Guinness World Records.
    — ABC News, ABC News, 4 July 2026
Definition of speed
Noun
  • History fans should look out for the climb up to the Château de Montségur, once a stronghold of the Cathar religious rebels, and scene of a bloody siege in 1244.
    — Jacob Whitehead, New York Times, 1 July 2026
  • According to the indictment made public this week, the Hoovers had strongholds over specific hotels and motels in their territory, including the Stadium Inn & Spas.
    — Brittny Mejia, Los Angeles Times, 1 July 2026
Definition of stronghold
Noun
  • The combined airline will eventually operate under the Allegiant brand, with changes to booking, loyalty and the travel experience still ahead.
    — Zach Wichter, USA Today, 7 July 2026
  • Out of loyalty to her father, Rhaenyra refuses, eventually deciding to send him north to the Wall.
    — Amanda Whiting, Vulture, 6 July 2026
Definition of loyalty
Noun
  • The underwater navigation itself is also power-hungry, as the robot has to rely on inertial sensors and acoustic Doppler velocity logging to track its position, since satellite navigation is useless once it's submerged.
    — New Atlas, New Atlas, 5 July 2026
  • Gage’s velocity noticeably declined towards the tail end of his outing.
    — Justice delos Santos, Mercury News, 4 July 2026
Definition of velocity
Noun
  • Was a wedding at that hulking fortress in Midtown Manhattan gauche?
    — Melissa Ruggieri, USA Today, 4 July 2026
  • The footage opens with fortress-like coastal imagery before moving into large-scale period sets, suggesting the film will have the epic scope of Hugo’s story while grounding it in a raw visual language.
    — Elsa Keslassy, Variety, 2 July 2026
Definition of fortress
Noun
  • Beginning on that day, Mercury invites everyone - creators, agencies, executives, and follow networks - to pledge their allegiance to Independent Podcasters Day via their website.
    — Frank Racioppi, Forbes.com, 2 July 2026
  • Gabriel Zakuani, the former Peterborough United defender who made 29 appearances for DR Congo in the previous decade, played an important role in convincing Wan-Bissaka to switch international allegiance.
    — Roshane Thomas, New York Times, 2 July 2026
Definition of allegiance
Noun
  • Because Cook County and the city of Chicago remain a Democratic bastion, new voters will not have the choice of getting new ideas or a fresh set of eyes from an independent or a Republican candidate.
    — Chicago Tribune, Chicago Tribune, 26 June 2026
  • These organizations claim to be bastions of journalism, Defenders of Democracy, and heroes in the fight for truth in government.
    — Ian Miller OutKick, FOXNews.com, 22 June 2026
Definition of bastion
Noun
  • Bishop Lawrence Sullivan invited the roughly 100 worshippers at the memorial’s dedication service to rise and pray.
    — Angie Leventis Lourgos, Chicago Tribune, 5 July 2026
  • The Cubs are honoring his unwavering dedication by permanently affixing his name to his Section 18 seats.
    — Peter Chawaga, Forbes.com, 5 July 2026
Definition of dedication

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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 7 Jul. 2026.

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