asperity
grimness
hardship
rigor
rigorousness
rigour
rigourousness
severeness
severity
austerity
calmness
coldness
exasperation
ferocity
firmness
gentleness
hardness
harshness
haughtiness
inflexibility
resolve
reticence
roughness
sadness
seriousness
sharpness
solemnity
vehemence
wistfulness
furnace