Extreme

From Old French extreme, from Latin extremus, the superlative of exterus

Full definition of extreme

Of a place, the most remote, farthest or outermost.
At the extreme edges, the coating is very thin.
In the greatest or highest degree; intense.

1918, W. B. Maxwell, The Mirror and the Lamp Chapter 13, And Vickers launched forth into a tirade very different from his platform utterances. He spoke with extreme contempt of the dense stupidity exhibited on all occasions by the working classes. He said that if you wanted to do anything for them, you must rule them, not pamper them.

2013-03, Frank Fish, George Lauder, Not Just Going with the Flow, An extreme version of vorticity is a vortex. The vortex is a spinning, cyclonic mass of fluid, which can be observed in the rotation of water going down a drain, as well as in smoke rings, tornados and hurricanes.

His extreme love of model trains showed in the rails that criscrossed his entire home.
Drastic, or of great severity.
I think the new laws are extreme, but many believe them necessary for national security.
Of sports, difficult or dangerous; performed in a hazardous environment.
Television has begun to reflect the growing popularity of extreme sports such as bungee jumping and skateboarding.
(archaic) Ultimate, final or last.the extreme hour of life

(plural extremes)

1898, Winston Churchill, The Celebrity Chapter 2, Sunning himself on the board steps, I saw for the first time Mr. Farquhar Fenelon Cooke....A silver snaffle on a heavy leather watch guard which connected the pockets of his corduroy waistcoat, together with a huge gold stirrup in his Ascot tie, sufficiently proclaimed his tastes....But withal there was a perceptible acumen about the man which was puzzling in the extreme.

Each of the things at opposite ends of a range or scale.
extremes of temperature
A drastic expedient.
(mathematics) Either of the two numbers at the ends of a proportion, as 1 and 6 in 1:2=3:6.

1796 Charles Burney, Memoirs of the Life and Writings of Metastasio 2.5:In the empty and extreme cold theatre.