Simple Definition of ultra-

from our Learner's Dictionary

ultra-

prefix

ˌʌltrə
1
: beyond : extremely : more than is usual
ultramodern
ultraserious
2
technical : beyond the range or limits of
ultraviolet
ultrasonic

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“Ultra-.” Merriam-Webster.com Simple Definition, Merriam-Webster, https://www.merriam-webster.com/simple/ultra-. Accessed 16 Apr. 2026.

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