adjective. Having made no preparations.

adjective. Not equipped to meet a contingency.

adjective. Impromptu.

Not prepared.

Not fitted or made suitable, fit, or ready for future use: as, unprepared provisions.

Not brought into a right, safe, or suitable condition in view of a future event, contingency, accident, attack, danger, or the like; not put in order; specifically, not made ready or fit for death or eternity.

Not planned; not worked out in advance; extemporaneous; as, an unprepared speech; unprepared speaking, Not brought into a particular mental state; not trained: as, an unprepared student.

In music, specifically of a dissonant tone, not held over from a preceding chord or otherwise prepared; reached by a skip.

adjective. Not prepared; caught by surprise.

adjective. without preparation; not prepared for

"So many children are being born in unprepared and immature families."

ad-lib  extemporaneous  extemporary  extempore  impromptu  

aired  bared  blared  cared  chaired  

defenseless  impracticable  incompetent  inexperienced  insufficient  

a bit previous  ad-lib  advanced  airy  amateurish