nidan verb (lower class) with 'yu' ending (archaic), intransitive verb
to partially heal; to get a bit better
Archaic intransitive verb meaning to recover partially from illness or injury. Found only in classical Japanese; not used in modern language.
古語の「おろいゆ」は、病が少し良くなることを表した。
The archaic word 'oroiyu' meant that an illness got a little better.