先天不足

xiāntiānbùzú
to suffer from a congenital deficiency; to have an inherent weakness

CEDICT

congenital deficiency; inherent weakness

Wiktionary

天生体质虚弱不足。亦泛指事物基础薄弱不稳固。

重編國語辭典

Entry Composition

1 先天 xiāntiān
  1. embryonic period (contrasted with 后天 hòutiān)
  2. inborn; innate; natural
2 不足 bùzú
  1. insufficient
  2. lacking
  3. deficiency
  4. not enough
  5. inadequate
  6. not worth
  7. cannot
  8. should not

Containing this entry

先天不足，后天失调 xiāntiānbùzú,hòutiānshītiáo
  1. to be born with a weak constitution and suffer from ill health during one's life
  2. (fig.) to be problematic from the start, and get even worse over time