extemporaneous
adjective
[ ɪkˌstɛmpəˈreɪnɪəs ]
• spoken or done without preparation.
• "an extemporaneous speech"
Similar:
extempore,
extemporary,
impromptu,
spontaneous,
unscripted,
ad lib,
on-the-spot,
improvised,
improvisatory,
unrehearsed,
unplanned,
unprepared,
unarranged,
unpremeditated,
makeshift,
thrown together,
cobbled together,
off-the-cuff,
spur-of-the-moment,
off the top of one's head,
Opposite:
rehearsed,
planned,
