What does whitelist mean?
Whitelist is a noun and verb for a list of approved or permitted people, organizations, systems, or other items, and for the act of adding or authorizing an entry on that list. It is especially common in computing, where software applications, email addresses, websites, or IP addresses may be permitted only if they appear on a security whitelist. As a verb, whitelist can mean either adding something to the list or granting it access, depending on context. The word was traditionally contrasted with blacklist, a list of excluded or denied entries. As inclusive terminology has become more common in technology and public institutions, allowlist is increasingly preferred because it explains the list's purpose without relying on a traditional association between white and positive status and black and negative status. Even so, whitelist remains familiar and is still encountered in technical documentation, older software, and formal policies.
A list of people, items, or systems that are approved, permitted, or authorized, especially for access to a computer system or service.
"The address was not on the email whitelist and was automatically rejected."
Allowlist is now often preferred in inclusive terminology, although whitelist remains common in technical contexts.
To add someone or something to an approved or permitted list, especially to authorize access to a system or service.
"The administrator whitelisted the contractor's account for the duration of the project."
The verb retains its older sense of placing an entry on an approved list as well as the modern sense of authorizing access.
The standard plural is used for separate lists or collections of approved entries.
"The organization maintains separate whitelists for each internal service."
Whitelist was once the standard term for a list of trusted users, but modern security teams increasingly call it an allowlist because it states its purpose without relying on the idea of white as inherently good.
Reviewed by Deb Chak, Editor. AI-assisted content curated by RJS Tech Solutions LLP.
Where does whitelist come from?
The expression dates from the early 17th century, when a white list was a list of people or matters regarded as acceptable, innocent, or approved. It combined white in a favorable sense with list, meaning a catalog or roll, and was originally contrasted with a blacklist. During the 20th century, its meaning expanded in administration and computing, and the verb developed from the noun's older sense of appearing on an approved list.
Related word forms
How whitelist is actually used
Whitelist remains widely recognized, especially in computing and security, but many organizations now prefer allowlist because it describes the list's function more directly and avoids language associated with racial exclusion. The older term blacklist has likewise been increasingly replaced by blocklist or denylist.