Billable time refers to the hours spent on a project or task that can be charged to a client or customer. There are many synonyms for this term, including chargeable hours, billable hours, billable work, client-billable time, and customer chargeable time. Other terms that can be used to describe this concept include revenue-generating hours, billable activity, billable services, paid work, and customer-billed time. These terms are commonly used in fields such as accounting, law, consulting, and creative services. Regardless of the term used, the goal is to accurately track and bill for the time spent on client work in a transparent and fair manner.