Headstrong and Spur-of-the-moment

Headstrong adjective - Given to resisting control or discipline by others.

Spur-of-the-moment and headstrong are semantically related. In some cases you can use "Spur-of-the-moment" instead an adjective "Headstrong".

Spur-of-the-moment adjective - Made or done without previous thought or preparation.

Headstrong and spur-of-the-moment are semantically related. Sometimes you can use "Headstrong" instead an adjective phrase "Spur-of-the-moment".