What does accessorily mean?
"Accessorily" is a formal English adverb meaning "in a subordinate or incidental manner" — that is, done or added as something auxiliary rather than essential. It is the adverbial form of "accessory," itself derived from Latin roots meaning an addition or accompaniment. The word appears mainly in legal, scholarly, and older literary texts, where it signals that a clause, condition, or action plays a supporting role alongside a principal one: a fee charged accessorily to a main transaction, or a detail mentioned accessorily in passing. Because it is uncommon even among educated readers, it carries a distinctly formal, slightly archaic flavor, and modern writers typically prefer plainer alternatives such as "incidentally" or "secondarily." Its rarity makes it useful precisely when a writer wants to mark something unmistakably as peripheral — and it offers a neat reminder of how English can build adverbs from almost any adjective, however obscure.
adverbIn a subordinate or auxiliary manner; as something additional or incidental rather than essential.
- In a subordinate, auxiliary, or incidental manner; as an addition rather than as the main thing.
"The clause was included accessorily, without any bearing on the main terms of the contract."
"The tax was levied accessorily, attached to the sale rather than imposed directly."
"She mentioned, only accessorily, that she had once lived in Vienna."
So rare that most dictionaries barely list it, "accessorily" is what you get when you turn "accessory" into an adverb — grammar's quiet back door.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Etymology of accessorily
"Accessorily" derives from "accessory," which comes from the medieval Latin "accessorius," formed on "accessio" (an accession or addition), ultimately from the Latin verb "accedere," "to approach or be added to." The adverb was formed in English by adding the regular adverbial suffix "-ly" to the adjective. It shares its root with such words as "access," "accession," and "accessible," all tracing back to the same Latin verb.
Related word forms
How accessorily is actually used
Formal and distinctly rare; found chiefly in legal, academic, and older prose. In everyday writing, writers almost always reach for "incidentally" or "secondarily" instead.
Easily confused with accessorily
"Accessory" is the noun or adjective for something added or subordinate (or an accomplice), while "accessorily" is the rarer adverb describing how something is done in that incidental, secondary way.