UNPREPARED
unprepared
(adjective) without preparation; not prepared for; “unprepared remarks”; “the shock was unprepared”; “our treaty makers approached their immensely difficult problems unprepared”- R.E.Danielson
Source: WordNet® 3.1
Etymology
Adjective
unprepared (comparative more unprepared, superlative most unprepared)
Not prepared; caught by surprise.
Noun
unprepared (plural unprepareds)
A black mark given to a pupil who arrives at a lesson without the necessary items or preparation.
Source: Wiktionary