dǐ​xì

background

底细 (底細) dǐ​xì
background noun
Inside information, background details, or the true state of affairs regarding a person or situation.

Before doing business with him, you'd better find out about his background.

Frequency

Movie subtitles
2.33 per million appears in 1% of films
Written text
1.69 per million

Sources

Definitions
CC-CEDICT