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"robust" is also used as a crossword clue. If that's what you saw, the answer is often hardy (5 letters).
Definitions
Strong, healthy, and able to withstand stress.
Word origin
Learned borrowing from Latin rōbustus.
Used in a sentence
“He was a robust man of six feet four.”
“robust health”
“A robust wall was put up.”
Source: Wiktionary, CC BY-SA 4.0
Used as a crossword answer2 curated clues
01“Strong and vigorous”6 letters
02“Strong and sturdy”6 letters
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