adjective / verb / adverb
free
FREE/friː/
Not bound by control, restraint, or obligation.
The bird is free as it flies through the open cage door toward the sky.
Etymology
Old English freo already described people not in bondage or acting by their own will. The payment sense extends the idea of exemption: something free is free of cost.
In context
they should have been out in the wild living and roaming free not confined in small cages