Definify.com
Webster 1913 Edition
Fieriness
Fi′er-i-ness
,Noun.
 The quality of being fiery; heat; acrimony; irritability; 
as, a 
. fieriness 
of temperAddison.
 Webster 1828 Edition
Fieriness
FI'ERINESS
,Noun.
  1.
  The quality of being fiery; hear; acrimony; the quality of a substance that excites a sensation of heat.2.
  Heat of temper; irritability; as fieriness of temper.