1. Most remote in any direction; outermost or farthest: the extreme edge of the field.
2. Being in or attaining the greatest or highest degree; very intense: extreme pleasure; extreme pain.
3. Being far beyond the norm: an extreme conservative. See Synonyms at excessive.
4. Of the greatest severity; drastic: took extreme measures to conserve fuel.
a. Characterized by severe, usually oxygen-poor environmental conditions.
b. Having an affinity for such conditions: an extreme microorganism.
a. Very dangerous or difficult: extreme rafting.
b. Participating or tending to participate in a very dangerous or difficult sport: an extreme skier.
7. Archaic Final; last.
1. The greatest or utmost degree or point.
2. Either of the two things situated at opposite ends of a range: the extremes of boiling and freezing.
3. An extreme condition.
4. An immoderate, drastic expedient: resorted to extremes in the emergency.
a. The first or last term of a ratio or a series.
b. A maximum or minimum value of a function.
6. Logic The major or minor term of a syllogism.
in the extreme
To an extreme degree: eccentric in the extreme.
[Middle English, from Old French, from Latin extrēmus; see eghs in the Appendix of Indo-European roots.]
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