Improvisational and Ill-advised

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

Ill-advised and improvisational are semantically related. In some cases you can use "Ill-advised" instead an adjective "Improvisational".

Ill-advised adjective - Showing poor judgment especially in personal relationships or social situations.

Improvisational and ill-advised are semantically related. Sometimes you can use "Improvisational" instead an adjective phrase "Ill-advised".