密探

mìtàn
  1. secret agent
  2. detective
  3. covert investigator

CEDICT

secret agent; spy

Wiktionary

從事祕密偵探工作的人。

重編國語辭典

Entry Composition

1 密 mì
  1. dense; close; thick
  2. intimate; close
  3. (bound form) secret; confidential
  4. (Internet slang) to send a private message to (sb); to DM
2 探 tàn
  1. to explore
  2. to search out
  3. to scout
  4. to visit
  5. to stretch forward

Related entries

暗探 àntàn
  1. secret agent
  2. detective
偵察員 zhēncháyuán
  1. detective
  2. investigator
  3. scout
  4. spy
偵探 zhēntàn
  1. detective
  2. to do detective work
两个侦探跟着嫌疑人。

Two detectives followed the suspect.

Source: Tatoeba

包探 bāotàn detective (in former times)
探員 tànyuán
  1. detective
  2. investigator
  3. agent
探長 tànzhǎng (police) detective
探子 tànzi
  1. intelligence gatherer
  2. spy
  3. detective
  4. scout
  5. sound (medical instrument)
  6. long and narrow probing and sampling utensil