Radical is someone who goes against social norms and who often advocates social change.(noun)
An example of a radical was a hippie in the 1960's.
The definition of radical is something that is at the root of something, or something that changes, addresses or affects the major essence of something.(adjective)
See radical in Webster's New World College Dictionary
Origin: ME < LL radicalis < L radix (gen. radicis), root
See radical in American Heritage Dictionary 4
Origin: Middle English, of a root
Origin: , from Late Latin rādīcālis, having roots
Origin: , from Latin rādīx, rādīc-, root; see wrād- in Indo-European roots.
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