
radikal
radical
Fundamental, complete, and far-reaching. Often describes a change or solution that gets to the root of a problem.
Die neue Regierung plant eine radikale Steuerreform.
The new government is planning a radical tax reform.
radical
Loading your saved state.

radical
Fundamental, complete, and far-reaching. Often describes a change or solution that gets to the root of a problem.
Die neue Regierung plant eine radikale Steuerreform.
The new government is planning a radical tax reform.

radical
Having an extreme political or social attitude that rejects the existing system and is often uncompromising.
Die Gruppe ist für ihre radikalen Ansichten und Forderungen bekannt.
The group is known for its radical views and demands.
The word 'radikal' (radical) comes from the Latin 'radix', meaning 'root'. A radical solution or change is therefore one that 'gets to the root' of a problem and addresses it fundamentally.
Er schlug eine radikale Vereinfachung der Bürokratie vor.
He proposed a radical simplification of the bureaucracy.
'Radikal' (radical) can be neutral ('fundamental') or negative ('extremist'). In connection with solutions, reforms, or changes, it is often neutral. In a political or social context, it more often has a negative connotation and describes uncompromising positions.
Die Firma plant eine radikale Umstrukturierung.
The company is planning a radical restructuring.
In the meaning 'fundamental', 'radikal' (radical) is often combined with nouns that describe a change. Common combinations are 'eine radikale Reform' (a radical reform), 'eine radikale Änderung' (a radical change), or 'ein radikaler Schnitt' (a radical cut/break).
Nach der Trennung entschied sie sich für einen radikalen Haarschnitt.
After the breakup, she decided to get a radical haircut.
The word family also includes the noun 'die Radikalität' (radicalism/radicality) and the verb 'sich radikalisieren' (to become radicalized). The verb in particular is often used in a political context to describe the development toward extreme views.
Man befürchtet, dass sich einige Jugendliche im Internet radikalisieren.
There are fears that some young people are becoming radicalized online.
extreme
Both words can describe a political position far toward the outer end of the spectrum. „Extrem“ mainly identifies the most extreme position, whereas „radikal“ additionally suggests rejecting the existing system and intending uncompromising change. Use „extrem“ when the degree is the focus, and „radikal“ when this attitude is also meant.

Die Partei vertritt eine radikale politische Position und lehnt das bestehende System ab.
The party holds a radical political position and rejects the existing system.
Die Partei vertritt eine extrem rechte politische Position.
The party holds an extreme right-wing political position.