noun
indefatigability; unyielding spirit
A yojijukugo describing a person who never gives up despite repeated failures or setbacks. Often used in formal or literary contexts to praise perseverance.
彼の百折不撓の精神が、ついに難事業を成功させた。
His unyielding spirit finally brought the difficult project to success.
If you keep making indefatigable efforts, your dream will come true someday.