私通

sītōng
  1. to have secret ties with
  2. to be in covert communication with (the enemy etc)
  3. to engage in an illicit sexual relationship
  4. adultery

CEDICT

  1. to commit adultery
  2. to have secret communication with

Wiktionary

  1. 祕密通好、勾結。
  2. 除娼妓外，非夫婦間的淫行，稱為「私通」。

重編國語辭典

Entry Composition

1 私 sī
  1. personal
  2. private
  3. selfish
2 通 tōng
  1. to go through
  2. to know well
  3. (suffix) expert
  4. to connect
  5. to communicate
  6. open
  7. to clear
  8. classifier for letters, telegrams, phone calls etc

Related entries

姦情 jiānqíng adultery
通姦 tōngjiān
  1. adultery
  2. to commit adultery
姦 jiān
  1. to fornicate
  2. to defile
  3. adultery
  4. rape