IPA: /mægˈnɪfɪsəntli/
KK: /mægˈnɪfɪsəntli/
In a way that is grand, impressive, or beautiful.
The castle was decorated magnificently for the royal banquet.
Magnificently → It is formed from "magnificus" (from Latin, meaning great or splendid) and the suffix "-ly" (meaning in a manner of). The word "magnificently" means in a manner that is great or splendid.
Think of something being done in a 'great' way ('magnificus') — that's why magnificently means doing something splendidly.