一部分

yībùfen
  1. portion
  2. part of
  3. subset

CEDICT

Entry Composition

1 一 yī
  1. one
  2. single
  3. a (article)
  4. as soon as
  5. entire; whole; all; throughout
  6. "one" radical in Chinese characters (Kangxi radical 1)
  7. also pr. yāo for greater clarity when spelling out numbers digit by digit
2 部分 bùfen
  1. part; portion; piece
  2. Taiwan pr. bùfèn