improvisation

n. act of improvising; something which is done without preparation, something improvised (i.e. speech or musical performance)

Improvisation is the practice of acting and reacting, of making and creating, in the moment and in response to the stimulus of one's immediate environment. This can result in the invention of new thought patterns, new practices, new structures or symbols, and/or new ways to act. This invention cycle occurs most effectively when the practitioner has a thorough intuitive or technical understanding of the necessary skills and concerns within the improvised domain.
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Noun
1. a creation spoken or written or composed extemporaneously (without prior preparation)
(hypernym) creation
(derivation) improvise, improvize, ad-lib, extemporize, extemporise
2. an unplanned expedient
(synonym) temporary expedient
(hypernym) expedient
(derivation) improvise, extemporize
3. a performance given extempore without planning or preparation
(synonym) extemporization, extemporisation
(hypernym) performance
(derivation) improvise, improvize, ad-lib, extemporize, extemporise

n. improvisation, act of improvising; something which is done without preparation, something improvised (i.e. speech or musical performance)

n. improvisation, improvising; ad-lib