fastness vs secureness

fastness and secureness both are nouns.

Word	Noun	Adjective	Verb	Adverb
fastness	Yes	No	No	No
secureness	Yes	No	No	No

As nouns, fastness and secureness are synonyms defined as:

fastness and secureness: the quality of being fixed in place as by some firm attachment

Other synonyms of fastness include fixedness, fixity, fixture.

fastness (noun)	secureness (noun)
a strongly fortified defensive structure	the quality of being fixed in place as by some firm attachment
a rate (usually rapid) at which something happens	the state of freedom from fear or danger
the quality of being fixed in place as by some firm attachment