apple cart

[HersheySoldier]

I just have done one of the exercises about English slang words and I came across the
term "apple cart" what does that mena? Here is the context:
Did you hear that the warehouse workers are trying to form a union at this company? That is sure to upset the apple cart around here," Lisa told Linus.

Bernd

[Nitikasnv3]

Hi,

Apple Cart:The planning that is disrupted when someone 'upsets the applecart'

i hope i have given satisfied answer.

Thanks