A huge robot with an array of weaponry ranging from frying pans to lasers. Most of his moves have almost no start up time and zero hangtime with the application of an advanced technique known as fast fly.

With the acquisition of unfly mode, be prepared to be perpetually stomped, frying panned, laser beamed and hyper sentinel forced. One mistake on sentinel will cost you 80% of your life. A huge robot that is feared by scrubs.
1) Sentinel just owned magneto, storm, and psylock without getting a scratch!!

Random Scrub:
"Damn he's using sentinel that guy's so cheap!"
by Big Paper February 8, 2005
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A mafia car, that resembles a BMW, from the popular game series Grand Theft Auto.
I was cruising down Trenton and saw a Sentinel so I had to jump out my ride to steal that whip.
by murphy06 April 7, 2008
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An outpost of understanding/cognizance/warning
Clarke's "The Sentinel"-1948
and "2001"
by NBNoG April 29, 2008
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Besides it's traditional English meaning:

The "squiddies" of the 'Matrix' -- And one of the two primary forms of antagonists in the films and universe
Sentinels are best avoided
by Depherios July 13, 2004
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Internet handle for one of the coolest guys around -- Johnny Spazz, or "J" to the "G" (me). Longest stay is at guitar.com: 2000-
Sentinel spends way too much time on misc using photoshop and laming it up.
by john griffin May 29, 2004
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roblox eggsploit sexy hot with cumstainality
omg omg sentinel is hot! #SentinelV3When
by Thatlodnd November 30, 2020
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A word that has no ture definiton because of the fact that it means so many different things. When you use this word in a conversation the only way for it to make sense is for the other person to at least be somewhat knowlegeable in the topic you are talking about. It usually is something that you will find in a video game. In one case Sentinel is actually the name of a video game for ps1. If you use this word when talking to someone about video games that isn't very knowlegeable but pretends they know what they are talking about, they will not even think for a split-second that what your are saying isn't true. Even people who know video games might get fooled if you just slip this wor din to your conversation because of normal it will sound. Typing this word in on google will bring up 7,500,000 links. This pretty much speaks for itself.
In 007 the sentinel is a missle launcher, In GTA the sentinel is a car,
In Halo the sentinels are flying machines that attack with laser-like weapons,
In Half-life the sentile is a machine gun,
Im sure in at least a few games out there besides Halo where there is an enemy(s) known as the Sentinel. If I wasn't so lazy I could probably find more examples via google (holy shit 7,500,000 links!) As you can see there is no true definiton for sentinel.
by bob is your aunt May 26, 2005
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