English can be a pretty versatile language. With the ability to write a given sentence in various ways, it can be hard to know which is grammatically correct. For example, if you find a sale that reduces the price of something, should you say that there is a “discount on” or a “discount off” the usual price?
Some people claim you should say “discount on” because you put a lower price on an item. Others, however, claim that because you are taking the price off of an item, you should say “discount off.”
Which One Is It?
In reality, it is more correct to say “discount on.” This conclusion is based on the “discount’s” true meaning. “Discount” is defined as a deduction from a full amount. This means that the term itself already says “off.”
With this, saying “a discount off” is technically repetitive, as you are saying “off” twice in the same sentence.
Many sources support this ruling, showing its truth and validity. However, many people still will like to say “off” because it can just roll off the tongue. While you can technically do this, it is always most correct to say “discount on.”
What Does Google Say?
A simple search of the two phrases using Google’s Ngram Viewer reveals that the “on” variation is by far more popular, as this graph shows:
Related: Substitute For or With?