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
Related Words clip
; warp speed
a structure or place from which one can resist attack <the guerillas retreated to their network of hidden fastnesses deep within the mountains>
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
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