na-adjective, noun
freely; unrestrained; as one pleases
Describes acting without constraint, moving in all directions, or doing something with complete freedom. Often used with verbs like 動く, 活躍する, or 使う.
彼はグラウンドを縦横無尽に走り回った。
He ran freely all over the field.
The new employee is showing unrestrained success.