\Un*fix"\, v. t. [1st pref. un- + fix.] 1. To loosen from a fastening; to detach from anything that holds; to unsettle; as, to unfix a bayonet; to unfix the mind or affections. 2. To make fluid; to dissolve. [R.] The mountain stands; nor can the rising sun Unfix her frosts. --Dryden.