extremely glorious; having or worthy of immense pride.

Theists should learn to be more careful before attempting to claim such an illustrious thinker as their own.
by Richard Weick August 31, 2007
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n. A member of the Ngai clan, descended directly from Genghis Khan, especially one who is able to do splits and has a friend who is a prince.
That Alexander is a real Illustrious Ngai, I bet he knows a prince.
by littlemy October 29, 2003
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