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

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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 The redyed fabrics showed uniform color uptake and washing and rubbing fastness comparable to the reference fabric, according to the study. — Alexandra Harrell, Footwear News, 26 Aug. 2026 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
  • Nearly everyone rides a stationary bike — high tension, low speed — after a match and quickly downs a protein recovery drink.
    — Matthew Futterman, New York Times, 6 Sep. 2026
  • The storm, now moving west-northwest at just 5 mph, is forecast to turn northward to north-northeastward with an increase in forward speed Sunday and Monday, the National Hurricane Center said in its latest update.
    — Doyle Rice, USA Today, 5 Sep. 2026
Definition of speed
Noun
  • During the final phase of the war in Gaza, Israel and the United States caused significant military and economic damage to Houthi strongholds in Yemen.
    — April Longley Alley, Foreign Affairs, 11 Sep. 2026
  • The rebels reported 48 airstrikes over 12 hours in the provinces of Jawf, Marib, Hodeida, Taiz, Bayda and Saada, the rebels' stronghold on the border with Saudi Arabia.
    — Arkansas Online, Arkansas Online, 10 Sep. 2026
Definition of stronghold
Noun
  • Doing so required a heavy dose of grit with a side of loyalty, exactly how his late father, his mother and all those people in Timber Lake taught him to live.
    — Matt Schneidman, New York Times, 8 Sep. 2026
  • Rather than directly monetizing the platform, Nvidia can deepen developer loyalty, make its hardware and software a natural choice for deploying AI models, and keep a strategic asset out of competitors' hands.
    — Alexa LoMonaco, CNBC, 5 Sep. 2026
Definition of loyalty
Noun
  • The rocket’s second stage ignited a single Aquila engine and accelerated to orbital velocity—some 5 miles per second—about seven minutes into the flight.
    — Stephen Clark, ArsTechnica, 6 Sep. 2026
  • The right-hander, who came to the Mets from the Milwaukee Brewers in the trade for Freddy Peralta, was the long man out of the bullpen at the start of the year and pitched well until his velocity started to decline.
    — Abbey Mastracco, New York Daily News, 6 Sep. 2026
Definition of velocity
Noun
  • Holding their accounts on freeze like a fortress are smarmy bank managers who laugh in the face of Beirut citizens who attempt a demand on their own funds.
    — Ryan Lattanzio, IndieWire, 4 Sep. 2026
  • Most of them can’t afford to outfit their own individual townhouses like armed fortresses as Swift has.
    — Bridget Read, Curbed, 1 Sep. 2026
Definition of fortress
Noun
  • The crowd at Melbourne Cricket Ground certainly had a mix of allegiance.
    — Matt Barrows, New York Times, 11 Sep. 2026
  • Just last month, a 35-year-old woman who pledged allegiance to ISIS and wanted to blow up the New York State Capitol building in Albany and also attack senators was arrested, authorities announced at a news conference in August.
    — Mark Morales, CNN Money, 10 Sep. 2026
Definition of allegiance
Noun
  • The problem is, these companies act much more like private enterprises than bastions of science.
    — Matthew Sun, The Atlantic, 4 Sep. 2026
  • In fact, as the world has become increasingly digital — reliant on laptops, tablets and the Notes app — the NFL remains a bastion of old-school note-taking.
    — Rustin Dodd, New York Times, 3 Sep. 2026
Definition of bastion
Noun
  • For all his disparate pursuits, Elsesser revels in the small details, incapable of giving anything less than total dedication.
    — Jeff Weiss, Los Angeles Times, 7 Sep. 2026
  • Before dismissing the jury, Sullivan thanked them for their dedication throughout the nearly six-week trial.
    — Marlene Lenthang, NBC news, 4 Sep. 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 14 Sep. 2026.

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