0 a person who has extreme political or religious opinions, or opinions that are more extreme than others in the same political party, etc.:
1 a running race that is longer than a marathon (= a race that is approximately 26 miles):
ultra-expensive
ultra-modern architecture
ultra-sensitive
an ultra-short haircut
ultra-cycling/ultra-running events
ultraconservative
ultramodern
4 used with adjectives to mean 'extremely':
These ultra-thin loudspeakers can be hidden as paintings on a wall.
The network uses ultra-fast fiber-optic cable.
The ultras were mounting their own campaign to unseat the senator.
As did the McCarthyites of the previous decade, the ultras argued vehemently that the real threat to the nation's security resided in communist subversion at home.
Banners for the Ultras of the Curva Nord (of Rome's Olympic stadium) were flying high.
From the central lower section of the north end the ultras fired flares and bellowed their anthem.
He needs to compete and win a lot of normal ultras before he could be classified as the best ever in that arena.
Ultrarunners are comfortable with extremes, and today the race has become one of the preeminent ultras in the country.
