1. a cart or stand used to sell apples, especially in a street market or fair
Usage: often used in the phrase 'upset the applecart'
2. a state of affairs or plan; used chiefly in the idiom 'upset the applecart' meaning to disrupt or ruin something
Usage: idiomatic; informal

Examples

• The farmer brought his applecart to the farmers' market every Saturday morning.
• Don't upset the applecart by changing the schedule at the last minute.
• She was careful not to upset the applecart during the delicate negotiations.
• The old applecart sat abandoned in the corner of the orchard.
• He upset the applecart when he revealed the surprise before the party.
• The street vendor's applecart was a familiar sight in the neighborhood.