firm; resilient; persevering
Describes something that is physically firm yet flexible, or a person who is mentally strong and persistent. Often used for noodles, paper, or a person's character.
See also: 腰の強い
These udon noodles are firm and chewy and delicious.
彼は腰が強いから、どんな困難にも負けない。
He is persevering, so he won't be defeated by any hardship.