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to paint over; to paint out; to fill in; to cover completely (with paint)
黒で全体を塗り潰した。
I painted the whole thing over in black.
壁の絵を塗り潰して白くした。
I painted over the picture on the wall and made it white.
失敗した部分を塗り潰すのに時間がかかった。
Covering up the mistakes took a long time.