Unfirmnes or Unfirmness: How To spell?

The word Unfirmnes is misspelled against Unfirmness, a noun meaning "Infirmness."

Unfirmness has double 'ss' in the end mispronounced as 's'
Remember double 'SS' appears in the end of this word which should not be misspelled with single 'S'
Wrong Spelling:  unfirmne-s 
Correct Spelling:  unfirmne-ss 
Find more wrongly spelled words of Unfirmness to spell it well.

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