What does accessorial mean?
Accessorial is a formal adjective with two distinct professional uses. In law, it describes conduct or liability that involves helping someone else commit a crime — the person who drives the getaway car bears accessorial rather than principal responsibility, since they aided the offence without committing its core act. In commerce, particularly freight and logistics, accessorial refers to supplementary services beyond basic point-to-point transport, such as liftgate assistance, inside delivery, or storage, which carriers bill as separate 'accessorial charges'. The word derives from Latin accessorius, meaning 'that which is added or subordinate', the same root behind accessory and accession. Because it belongs to technical vocabularies, accessorial rarely appears in casual conversation, but it is indispensable in legal analysis of complicity and in understanding how shipping invoices accumulate costs beyond the headline rate.
Relating to or involving aid given to the principal perpetrator of a crime; constituting secondary rather than primary liability.
"The prosecutor argued that supplying the lock picks was an accessorial act."
Chiefly legal; 'accessory' is the more familiar term in general use.
A charge levied for a supplementary service connected with the transportation of goods, beyond the basic freight rate.
"Detention fees are among the most contested accessorials in trucking contracts."
Used almost exclusively in freight, logistics, and supply-chain contexts.
The plural applies to the noun sense in freight contexts, where individual supplementary charges are itemized as 'accessorials'.
"The contract specifies all applicable accessorials, including fuel surcharges and stop-off fees."
In freight billing, 'accessorial charges' are the sneaky extra fees — liftgates, inside delivery, detention — that can quietly double your shipping invoice.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of accessorial
Accessorial comes from the Latin accessorius, meaning 'additional' or 'subordinate', itself formed from accedere ('to approach' or 'be added'), the root of English words such as access, accession, and accessory. The adjective entered English through legal usage, where it described acts of aiding or abetting a principal offender. Its later adoption in freight and logistics extends the same idea of something added on to a primary service.
How accessorial is actually used
Formal and technical in register; found mainly in legal writing and freight/logistics documentation. In everyday speech, 'accessory' is far more common for the criminal-aid sense.
Easily confused with accessorial
Accessory is the standard word for a person who aids a crime (or an item that complements something), while accessorial is the rarer adjective form describing the liability or character of such aid.
Accessary is a legal variant spelling of accessory referring to a person who assists an offence, whereas accessorial is an adjective describing conduct or liability of that kind.