Synonyms of fastness

Noun

1. speed, swiftness, fastness, pace, rate

usage: a rate (usually rapid) at which something happens; "the project advanced with gratifying speed"

2. fastness, fixedness, fixity, fixture, secureness, immovability, immovableness

usage: the quality of being fixed in place as by some firm attachment

3. stronghold, fastness, defensive structure, defense, defence

usage: a strongly fortified defensive structure

Definition and meaning of fastness (Dictionary)