The name Gabriel in the Bible
Gabriel is one of two named angels in the Bible; Michael is the other one. Of Michael we know that he's an archangel but of Gabriel we do not. Still Gabriel is a pretty important guy.
Gabriel explains to Daniel some of the most awesome visions contained in the Bible (Daniel 8:16 and 9:21), and, more than five centuries later, Gabriel (Γαβριηλ) announces to Zacharias and Mary their respective sons: John to be The Baptist and Jesus Christ (Luke 1:19, 26).
Gabriel himself submits that he stands in the presence of the Lord (Luke 1:19), which is no small thing, even though that has been promised to all of us (Jude 1:24).
Etymology of the name Gabriel
The first segment of the name Gabriel comes from the verb גבר (gabar), meaning to be mighty:
The English language (vastly inferior to Hebrew) knows plenty of amicable words for man (dude, bloke, chap, codger) but no words that describe him as a powerful creature without getting ridiculous (He-man, hunk, tiger). If such a word would ever be devised, the name Gabriel consists of it, plus the word El. For now, we must settle for a too simple Man Of God, or God's Guy.