Impromptu and Makeshift

Impromptu adjective - Made or done without previous thought or preparation.

Makeshift is a synonym for impromptu. In some cases you can use "Makeshift" instead the word "Impromptu" as an adjective or an adverb or a noun.

Makeshift adjective - Taking the place of one that came before.

Impromptu is a synonym for makeshift in temporary topic. You can use "Impromptu" instead the word "Makeshift" as an adjective or an adverb or a noun.