While marketers still primarily use “blacklist”, “blacklisted”, or “blacklisting” to describe the action of having IP addresses flagged by a blocklist, list providers use the term blocklist for the list itself. Providers like Return Path and Spamhaus offer blocklists to mailbox providers to aid in their filtering decisions. When a mailbox provider uses a blocklist to determine that the IPs should be blocked at the gateway, the action they are taking is blacklisting.
Although an IP may be listed on a blocklist, this doesn’t mean that it has been blacklisted. Return Path shares the Return Path Blocklist with filtering agencies, security companies and mailbox providers but does not control how the blocklist is used. Every provider has their own policies when it comes to blocklists. Therefore, each might use it differently.