What is musical term meaning loudly or powerfully?

Answer 1

There are all sorts of musical terms that mean "loudly" or "Powerfully", including loudly and powerfully!

The habit of using only Italian terms in music has largely passed, not least of causes being the German composers using German terms, the French using French terms, and English and American composers finally starting to use English terms.

For traditionalists, though, the Italian word that most nearly matches loudly or powerfully is "Forte".