In an invincible manner; unconquerably; insuperably.(adverb)
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Use "invincibly" in a sentence
"And he set himself then and there to smile invincibly, meaning to keep on smiling for fifty years at least -- the blind live long."
"What an ironic twist of fate, then, that he becomes teacher to a class containing his precise opposite, the invincibly positive-minded Fuura Kafuka. (from: ANN)"
"I am not arrogant or stupid enough to think I am invincibly right."