Something which sells really well is known as a 'bestseller.'
"Top of the bestseller list this month is An End to the Killing Spree by Bill O’Reilly."
In a large shop, there may be a few regular best selling items that invariably outsell other items. Or there may be seasonal variations such as at Christmas time when new products are in high demand and so for December become the top sellers of the month.
大ヒット商品のことをbestsellerと言います。
"Top of the bestseller list this month is An End to the Killing Spree by Bill O’Reilly."
大きな店では、数枚のCDの売上がその他の商品の売上を上回ることがある。
または、もしかするとクリスマスなど時期的な要因なのかもしれません、新商品の需要が伸びる12月は「the top seller of the month」と年間で売り上げがトップの月ということができます。
example
"This new soap range is proving to be our best seller."
or
"The new pizza range is proving to be the flavour of the month."
or
"This is our most popular product with our buyers."
"This new soap range is proving to be our best seller."
この新しいせっけんの種類はベストセラーです。
"The new pizza range is proving to be the flavour of the month."
このピザの種類は、今月売れています。
"This is our most popular product with our buyers."
これは、バイヤーに最も人気のある商品です。
You could use 'best seller', 'top seller' or even 'number 1 seller' and then follow this phrase with 'this month', 'this week', 'today', 'this year', 'this season' etc, to describe the amount of time it has been popular for.
When we advertise about the 'number one product of the month', we are advertising the most popular item of the store in that month.
Stores always keep statistics of every product and the popular ones usually go on special/sale and you can find them at great, discounted prices.
With this data, they are able to see which products are most popular in the store and which products they are better off no longer selling because the demand for the product is low.
number one product of the month' はその月で最も人気のあった商品をいいます。
お店は全ての商品について常にデータをとっていて、人気のものは特売で売り出されたりします。
こうしたデータから、そのお店でどの商品が売れているかや、あるいはどの商品が売れず需要がないかが分かります。
"Best seller" and "Top seller"
These two expressions are used when a product in a shop,restaurant etc, has been selling and is more popular than the other products.
ex. "This cocktail is this months best seller" and "Tom Yum Kung soup is the top seller today"
"Best seller" や"Top seller"は、お店の商品やレストランのメニューなどがほかの商品などに比べて売り上げがいいことを意味します。
例：
"This cocktail is this months best seller"
（このカクテルは今月のベストセラーです。）
"Tom Yum Kung soup is the top seller today"
（トムヤムクンスープは今日のトップセラーです。）
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