extemporaneous (adjective) extemporaneous: improvised
Detalii: extemporaneous means 'prepared in advance and carried out with few or no notes' while impromptu means 'totally unprepared, performed on the spur of the moment' - but this distinction has been all but lost
Sinonime: antecede, antedate, anticipate, be ahead of, come first, forerun, foreshadow, go before, go in advance, guide, harbinger, have a head start, head, head up, herald, in space, introduce, lead, light the way, outrank, pace, pave the way, pioneer, preexist, preface, presage, rank*, ring in, run ahead, scout, take precedence, time, usher
Antonime: deliberate,
planned, premeditated,
prepared, rehearsed