Words related to extreme
"situated or being outside, pertaining to or connected with that which is outside," 1520s, from Latin exterior "outward, outer, exterior," comparative of exterus "on the outside, outward, outer, of another country, foreign," itself a comparative of ex "out of" (see ex-). As a noun, "outer surface or aspect" from 1590s.
I would remind you that extremism in the defense of liberty is no vice! And let me remind you also that moderation in the pursuit of justice is no virtue. [Barry Goldwater (1909-1998), acceptance speech as Republican candidate for President, 1963]