Definition of unprosperousness in US English:

unprosperousness

noun

  • The quality or condition of being unprosperous; lack of prosperity or success.

Origin

Mid 17th century; earliest use found in John Bond (1612–1676), college head. From unprosperous + -ness, after prosperousness.

Pronunciation

unprosperousness

/(ˌ)ʌnˈprɒsp(ə)rəsnəs/