xiǎo​jīn​kù

private stash

小金库 (小金庫) xiǎo​jīn​kù
private stash noun
hidden reserve of money kept by an individual, often concealed from family members or a spouse
slush fund noun
unauthorized or secret pool of money kept by an organization or department outside official accounting

Frequency

Movie subtitles
0.060 per million appears in 0% of films
Written text
1.70 per million

Sources

Definitions
CC-CEDICT