Significantly means in a way that is great or important

[“significantly”, Oxford English Dictionary, , accessed 8-15-15, AFB]

significantly

See definition in Oxford Advanced Learner's Dictionary

Syllabification: sig·nif·i·cant·ly

Pronunciation: /səɡˈnifəkən(t)lē/

Definition of significantly in English:

adverb

1 In a sufficiently great or important way as to be worthy of attention:

energy bills have increased significantly this year

[AS SUBMODIFIER]: their situation is significantly different from ours