being able to do as one pleases; doing at will
pothook
pothook (for hanging a pot, etc. over a fire)
彼は英語を自在に操ることができる。
He can handle English freely.
自在に形を変えられる新素材が開発されました。
It's a material that can freely change shape.
自在に動ける健康な体を維持したいです。
I want to maintain a body that can move freely.