An ultraroyalist in France.
An extremist, especially an ultranationalist.
An especially devoted football fan, typically associated with the intimidating use of extremist slogans, pyrotechnics and sometimes hooligan violence.
An ultramarathon.
An ultra-prominent peak.
(usually capitalised) Code name used by British codebreakers during World War 2 for decrypted information gained from the enemy.
Extreme; far beyond the norm; fanatical; uncompromising.
an ultra reformer; ultra measures