Late Middle English; earliest use found in The Wycliffite Bible (early version). From un- + prudent, originally after classical Latin imprūdēnt-, imprūdēnsimprudent.
Definition of unprudent in US English:
unprudent
adjective(ˌ)ʌnˈpruːd(ə)nt
rare
Not prudent, unwise; = "imprudent".
Origin
Late Middle English; earliest use found in The Wycliffite Bible (early version). From un- + prudent, originally after classical Latin imprūdēnt-, imprūdēns imprudent.