Meaning one: outsourced bookkeeping under your name
In the service sense, a provider supplies bookkeepers who process your clients’ transactions, reconcile accounts and prepare reports. Your firm keeps the client relationship, reviews the output and presents it under its own name. Clients typically never deal with the provider. The appeal is capacity without hiring.
This arrangement says nothing, on its own, about software. The provider may work in whatever system your clients already use, or in one it prefers. Your brand appears on reports and emails you send, but the client may still sign in to a product carrying another company’s name.