1. relating to or being an accessory; supplementary or additional
Usage: legal; formal
2. relating to charges or services that are additional to the main service
Usage: business; transportation

Examples

• The shipping company charged accessorial fees for weekend delivery.
• Accessorial services like packaging and insurance cost extra.
• The contract included accessorial charges for fuel surcharges.
• Many trucking companies list their accessorial rates separately.
• The accessorial equipment was not covered under the basic warranty.
• Legal accessorial liability extends to those who aid in crimes.