radical

Arising from or going to a root or source; basic.

Departing markedly from the usual or customary; extreme or drastic.

Relating to or advocating fundamental or revolutionary changes in current practices, conditions, or institutions.

Relating to or being surgery that is extreme or drastic in an effort to eradicate all existing or potential disease.

Of or being a root.

Of, relating to, or arising from a root.

Arising from the base of a stem or from a below-ground stem or rhizome.

Excellent; wonderful.

One who advocates fundamental or revolutionary changes in current practices, conditions, or institutions.