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Significantly difference is the most popular phrase on the web.

significant difference 17,180,000 results on the web	Significantly difference 122,100,000 results on the web More popular!
Some examples and use cases from the internet:	Some examples and use cases from the internet:
Following the disclosure the applicant alleged that there was a significant difference between the market situation in North America and Ukraine. There is often a significant difference in temperature between the two masses. There's a fairly significant difference. However there was no significant difference during the maintenance phase. 10 A significant difference in overall survival time could not be shown in this study. The results showed no significant difference in the pharmacokinetics of bevacizumab in relation to age. There was a significant difference in dietary phenylalanine tolerance in the sapropterin treatment group as compared to the placebo group. There was no significant difference in effect between sildenafil doses.	It doesn't look like this phrase is very popular! The search could not find any examples on the internet.

significant difference

17,180,000 results on the web

Significantly difference

122,100,000 results on the web

More popular!

Following the disclosure the applicant alleged that there was a significant difference between the market situation in North America and Ukraine.
There is often a significant difference in temperature between the two masses.
There's a fairly significant difference.
However there was no significant difference during the maintenance phase.
10 A significant difference in overall survival time could not be shown in this study.
The results showed no significant difference in the pharmacokinetics of bevacizumab in relation to age.
There was a significant difference in dietary phenylalanine tolerance in the sapropterin treatment group as compared to the placebo group.
There was no significant difference in effect between sildenafil doses.

It doesn't look like this phrase is very popular! The search could not find any examples on the internet.