sound health; robust health; vigorous
Literary or somewhat formal word describing a person's strong, healthy constitution. Often used in set phrases like 勇健な体.
My grandfather is in robust health for a 90-year-old.
His vigorous body is the fruit of training in his youth.
Compound of 勇 (bravery, courage) and 健 (health, strength). The exact historical derivation is uncertain, but the combination conveys the idea of brave, vigorous health.