"No pain, no stain!"
-- slogan in product's advertisement at the 1994 Quidditch World Cup final (GF8)
A magical cleaning product.
"Scower" is a homonym for "scour", an English word meaning "to clean thoroughly".
In 1861, the book Mrs Beeton's Book of Household Management was published. This book was a guide for housewives to running a Victorian household. The book is quite famous -- and actually remains in print as of 2016. The name of the most popular wizarding cleaning product may have been suggested by the title of this book.
From the Web
Mrs Skower's All Purpose Magical Mess Remover from the Harry Potter Wiki
Mrs Beeton's Book of Household Management from Wikipedia