I'll never forget the look of Koichi's refined face.
Koichi is trying to polish a rough draft of his poetry for the poem contest in October.
I didn’t know that Salmon spoke in such refined Japanese like that.
You take your practice and you wash it. Slowly chunks fall off and it becomes more and more simple. You are washing away the gunk on the outside to attain refinement and polish yourself, via practice.
This is a jukugo word, which usually means on'yomi readings from the kanji. If you know the readings of your kanji you'll know how to read this as well.