出淤泥而不染

chūyūníérbùrǎn
  1. lit. to grow out of the mud unsullied (idiom)
  2. fig. to be principled and incorruptible

CEDICT

to rise out of the ghetto and make something of oneself; to have been in bad surroundings without allowing oneself to be affected by them.

Wiktionary

指莲花由水底的烂泥中长出，却依然清新、美丽。语出宋．周敦颐〈爱莲说〉。比喻一个人的言行有自己的原则，不会受坏环境的影响。

重編國語辭典

Entry Composition

=1 出 chū
  1. to go out; to come out
  2. to arise; to occur
  3. to produce; to yield
  4. to go beyond; to exceed
  5. (used after a verb to indicate an outward direction or a positive result)
  6. classifier for dramas, plays, operas etc
=1 出 chū variant of 出 chū (classifier for plays or chapters of classical novels)
2 淤泥 yūní
  1. silt
  2. sludge
  3. ooze
3 而 ér
  1. and
  2. as well as
  3. and so
  4. but (not)
  5. yet (not)
  6. (indicates causal relation)
  7. (indicates change of state)
  8. (indicates contrast)
4 不 bù
  1. no; not so
  2. (bound form) not; un-
5 染 rǎn
  1. to dye
  2. to catch (a disease)
  3. to acquire (bad habits etc)
  4. to contaminate
  5. to add color washes to a painting