at a moment's/minute's notice

:  a minute portion or point of time :  instant

:  a comparatively brief period of time

:  present time

:  the 60th part of an hour of time :  60 seconds

:  the 60th part of a degree of angular measure

:  the distance one can traverse in a minute

:  to make notes or a brief summary of

:  very small :  infinitesimal

:  of small importance :  trifling

:  marked by close attention to details

:  warning or intimation of something :  announcement

:  the announcement of a party's intention to quit an agreement or relation at a specified time

:  the condition of being warned or notified

:  to give notice of

:  to comment upon

:  review