Synset

with little or no preparation or forethought
<adj.all>   freq. cnt.: 2 freq. cnt.: 1 freq. cnt.: 1

ad-lib

extemporaneous

extemporary

extempore

impromptu

off-the-cuff

offhand

offhanded

unrehearsed

sample sentences

"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"