「Adjectives and Adverbs」
An adjective may be used as a noun by adding the suffix sa to the stem. The suffix mi may also be used with a limited number of i-adjectives.
「Adj stem ＋sa・さ」
The suffix sa added to the stem of an i- or na-adjective turns the adjective into a noun that expresses degree.
Kabe no shirosa ga heya o akaruku shita.
The whiteness of the walls brightened the room.
Kono ike no fukasa wa dono gurai desu ka.
What is the approximate depth of this pond?
Kare no taido no rippasa ni kanshin shita.
I was impressed by his fine attitude.
「Lit., The fineness of his attitude.」
Hope this helps!
°˖ ✧◝(○ ヮ ○)◜✧˖ °こゆうきあいはら°˖ ✧◝(○ ヮ ○)◜✧˖ °