unbound

Short definition from Wiktionary

Verb

1. 1
   simple past and past participle of unbind

Adjective

1. 1
   Not bound: Not obligated.
2. 2
   Not bound: Not tied up.
3. 3
   Not bound: Without a binding.
4. 4
   Not bound: Lying beyond the proton or neutron drip line; having a negative particle separation energy; capable of decaying by the spontaneous exothermic emission of one or more nucleons.