Longman Dictionary of Contemporary English
Douglas Harper's Etymology Dictionary
1865, verbal noun from message (v.).
Wiktionary
vb. (present participle of message English)
WordNet
n. the sending and processing of e-mail by computer [syn: electronic messaging]
Wikipedia
Usage examples of "messaging".
Our customers are in cars, at offices, on the Internet, watching one of hundreds of cable channels and new networks, listening to local and syndicated radio programs, playing interactive computer games, involved with CD-ROAU or electronic messaging, modems, fax broadcast services-the list is building daily.
Carson switched to GeneDyne's electronic messaging system and brought up the message.
Testing indicated that human messaging and coding of all types, including the genetic coding and sequencing, were channeled through this structure.
I decided to try instant messaging Michael, telling him I really needed to talk to Lilly and would he please go off-line so I could call her.
She was thankful she'd found him on this early in the evening and glad she'd exchanged instant messaging information with at least some of the chat group.
AOL had just shot past 15 million subscribers and was gobbling up CompuServe and ICQ, pioneers of instant messaging.
We don't exchange Christmas cards or share instant messaging, and he's totally out of my Rolodex.
Thought for a little while whilst pretending to study tedious-beyond-belief manuscript from lunatic Have never messaged Daniel Cleaver before but brilliant thing about messaging system is you can be really quite cheeky and informal, even to your boss.