noun
premature alopecia; early-onset hair loss
Medical term for hair loss occurring at a younger age than typical.
若年性脱毛症は、10代や20代で発症することがあります。
Premature alopecia can develop in one's teens or twenties.
General term for alopecia or hair loss; 若年性脱毛症 specifies early-onset cases.
Compound of 若年 (young age), 性 (nature/characteristic), and 脱毛症 (alopecia).