The genuine or full-scale way of doing something; indicating something being done properly or in earnest. Often used as 本格的.
この店は本格的なイタリア料理を出すと評判だ。
This restaurant is reputed to serve authentic Italian cuisine.
準備が整い、プロジェクトは本格的に始動した。
With preparations complete, the project started in earnest.
趣味で始めた陶芸を、本格的に学びたいと思っている。
I started pottery as a hobby, but now I want to study it seriously.