Synonyms for Redoubtable (same or very similar meaning)
WordNet sense 1 (having or worthy of pride):
glorious, illustrious, respected
WordNet sense 2 (feeling self-respect or pleasure in something by which you measure your self-worth; or being a reason for pride):
proud
WordNet sense 3 (inspiring fear):
formidable, unnerving
WordNet sense 4 (causing alarm or fear):
alarming
From the ODE community, based on WordNet
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