What is another word for on spur of moment?
Pronunciation: [ˌɒn spˈɜːɹ ɒv mˈə͡ʊmənt] (IPA) 
On spur of moment, or "impromptu" can be used to describe things that are done on a whim without much forethought. Other synonyms include "spontaneous," which means acting on impulse or without planning, "unplanned," which refers to something that is not designed or prepared in advance, and "off-the-cuff" which is an informal expression for something that is said or done without having been prepared or thought through. "Capricious" can also be a fitting synonym, and it refers to things which are subject to whim or random chance. Ultimately, these synonyms all describe things that are done without much preparation or thought, and often result in unpredictable or exciting outcomes.
