Jabber may refer to:
- The original name of the Extensible Messaging and Presence Protocol (XMPP), the open technology for instant messaging and presence.
- Jabber.org, the public, free instant messaging and presence service based on XMPP.
- Jabber XCP, a commercial product which is an implementation of XMPP. Acquired by Cisco Systems in 2008.
- An abnormally long transmission on an Ethernet network or link.