blog (n.)

"online journal," 1998, short for weblog (which is attested from 1993 but in the sense "file containing a detailed record of each request received by a web server"), from (World Wide) Web (n.) + log (n.2). Joe Bloggs (c. 1969) was British slang for "any hypothetical person" (compare U.S. equivalent Joe Blow); earlier blog meant "a servant boy" in one of the college houses (c. 1860, see Partridge, who describes this use as a "perversion of bloke"), and, as a verb, "to defeat" in schoolboy slang. The Blogger online publishing service was launched in 1999.

updated on April 09, 2018

Definitions of blog from WordNet
blog (v.)
read, write, or edit a shared on-line journal;
blog (n.)
a shared on-line journal where people can post diary entries about their personal experiences and hobbies;
postings on a blog are usually in chronological order
Synonyms: web log
Etymologies are not definitions. From, not affiliated with etymonline.