fast·​ness | \ ˈfas(t)-nəs How to pronounce fastness (audio) \

Definition of fastness

1 : the quality or state of being fast: such as
a : the quality or state of being fixed
b : the quality or state of being swift
c : colorfast quality
d : resistance (as of an organism) to the action of a usually toxic substance
2a : a fortified or secure place
b : a remote and secluded place vacationed in their mountain fastness

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Examples of fastness in a Sentence

the amazing fastness with which the boy took his shower had us wondering if he'd used any water the guerillas retreated to their network of hidden fastnesses deep within the mountains
Recent Examples on the Web Given their advance into Labour’s working-class fastness, the Tories’ worst nightmare is not a Labour Party that returns to the old centre as defined by Tony Blair. The Economist, "Bagehot Jeremy Corbyn’s crushing defeat," 13 Dec. 2019 The other tragedy occurred far from the public eye, in one of the last remote fastnesses of the world. Ipsita Chakravarty, Quartz India, "How colonialism cost the Himalayas their remoteness," 10 June 2019 Indeed, Lego can't reach its 2030 goal without solving ABS, a material that affords the company the attributes it so prizes: Durability, color fastness, strength, and clutch power, or how well two joined bricks stay together. Brian Barrett, WIRED, "Lego Builds a Sustainable Future, One Brick at a Time," 11 Mar. 2018 These enabled India to detect, and destroy by air, Pakistani troops entrenched in mountain fastnesses. Tunku Varadarajan, WSJ, "Modi and Netanyahu Begin a Beautiful Friendship," 5 July 2017 India kept the mostly Hindu rest of Jammu, the Vale itself and the desert-like fastness of Ladakh. The Economist, "Vale of darknessBuffeted by both India and Pakistan, it is the Kashmiris who suffer most," 20 July 2017

These example sentences are selected automatically from various online news sources to reflect current usage of the word 'fastness.' Views expressed in the examples do not represent the opinion of Merriam-Webster or its editors. Send us feedback.

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First Known Use of fastness

before the 12th century, in the meaning defined at sense 1

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Time Traveler for fastness

Time Traveler

The first known use of fastness was before the 12th century

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Cite this Entry

“Fastness.” Dictionary, Merriam-Webster, Accessed 15 Jul. 2020.

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How to pronounce fastness (audio)

English Language Learners Definition of fastness

literary : a place that is difficult to get to or that can be easily defended if it is attacked


fast·​ness | \ ˈfas(t)-nəs How to pronounce fastness (audio) \

Medical Definition of fastness

: resistance (as of an organism) to the action of a usually toxic substance streptomycin fastness developed by a strain of tubercule bacillus

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Rhyming Dictionary: Words that rhyme with fastness

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