extempore
ex tempore
ad lib
cold
unprepared
extemporarily
extemporaneously
ad libitum
impromptu
spontaneously
preparingly
off the cuff
unpredestinated
improvize
extemporize
extemporise
improvise
ad-lib
preparatively
noncontemporaneous
uncontemporaneous
ready-made
ad-libbed
off-the-cuff
off the top of one's head
unpracticed
extemporaneous
impracticable
nonmethodical
unmethodical
unrehearsed
nondysfunctional
offhand
offhanded
unsystematical
extemporary
nonresumptive
inefficaciously
unpractised
noniodized
unversed
postpreparative
nonroutine
unexpeditated
preparative
pretraining
indextrous
prepreparation
nonmanual
unsyringed