ex·tem·po·ra·ne·ous 
(ĭk-stĕm′pə-rānē-əs)
(ĭk-stĕm′pə-rānē-əs)adj.
1. Carried out or performed with little or no preparation; impromptu: an extemporaneous piano recital.
2. Prepared in advance but delivered without notes or text: an extemporaneous speech.
3. Skilled at or given to unrehearsed speech or performance: an accomplished extemporaneous speaker.
4. Provided, made, or adapted as an expedient; makeshift: an extemporaneous policy decision.
[From Late Latin extemporāneus, from Latin ex tempore; see EXTEMPORE.]
ex·tem′po·ra·nei·ty (-pər-ə-nēĭ-tē) n.
ex·tem′po·rane·ous·ly adv.
ex·tem′po·rane·ous·ness n.