Synonyms and Antonyms of fastness

  1. 1 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 celerity, speed, fleetness, haste, hurry, quickness, rapidity, rapidness, speediness, swiftness, velocityRelated Words clip, gait, pace, rate, tempo; drive, hustle; acceleration, hastiness, precipitation, precipitousness, rush; alacrity, dispatch, expedition, expeditiousness, promptitude, promptness; warp speedNear Antonyms languidness, languor, leisureliness, lethargy, torpidity, torpor; reluctance; deliberateness, deliberation; dilatoriness, lateness, pokiness, procrastinationAntonyms slowness, sluggishness

  2. 2 a structure or place from which one can resist attack <the guerillas retreated to their network of hidden fastnesses deep within the mountains> Synonyms bastion, castle, citadel, fort, fortification, fortress, hold, redoubt, strongholdRelated Words battlement, breastwork, bulwark, earthwork, embattlement, parapet, rampart; bunker, dugout; blockhouse, garrison house; alcazar, casbah (also kasbah)

  3. 3 adherence to something to which one is bound by a pledge or duty <his uncompromising fastness to the cause of freedom was beyond question> Synonyms adhesion, allegiance, attachment, commitment, constancy, dedication, devotedness, devotion, faith, faithfulness, fidelity, fealty, loyalty, piety, steadfastness, trothRelated Words affection, fondness; determination, firmness, resolution; dependability, reliability, trustability, trustiness, trustworthinessNear Antonyms alienation, disaffection, estrangement, separationAntonyms disloyalty, faithlessness, falseness, falsity, inconstancy, infidelity, perfidiousness, perfidy, treachery, unfaithfulness

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