extempore

(r) without prior preparation
- he spoke extemporaneously
extemporaneously, extemporarily,
(s) with little or no preparation or forethought
- his ad-lib comments showed poor judgment
- an extemporaneous piano recital
- an extemporary lecture
- an extempore skit
- an impromptu speech
- offhand excuses
- trying to sound offhanded and reassuring
- an off-the-cuff toast
- a few unrehearsed comments
ad-lib, extemporaneous, extemporary, impromptu, offhand, offhanded, off-the-cuff, unrehearsed,

extemporaneously extemporarily ad-lib extemporaneous extemporary impromptu offhand offhanded off-the-cuff unrehearsed