Ephemeral key
A cryptographic key is called ephemeral if it is generated for each execution of a key establishment process. In some cases ephemeral keys are used more than once, within a single session where the sender generates only one ephemeral key pair per message and the private key is combined separately with each recipient's public key. Contrast with a static key.Private ephemeral key agreement keys are the private keys of asymmetric key pairs that are used a single key establishment transaction to establish one or more keys and, optionally, other keying material.
