A guardian warrior of religon, to guard, or the act of being a guardian.
(1)The sentry stands alone, waiting for an enemy to come to close and fight.
(2)Is their a sentry lock on the doorknob.
(3)That empty car in the way provided a good sentry against the oncoming bus at the crowd of people.
by Mairsil October 10, 2008
A nickname a man usually over 40 would give a girl that has a very tight vagina. 1st mentioned by the rapper Too Short in the 80's classic rap song 'Freaky Tales': "...her **ssy was tighter than a Sentry Safe..."
Usually to a side chick: "How is my lil Sentry today? what you want? what you need?... huh? Some coffee from the Starbucks? ...So I gotta get up, get dressed real quick drive to the coffee joint then drive all the way to your work and drop it off?!... I'm on my way...make sure my lil Sentry get what she wants"
by Sound of a Clock Ticking March 2, 2017
Gaming term for any fully autonomous stationary weapon, or Sentry Turret. They have featured in many FPSs, most notably in the Valve games.
by Parsefone February 6, 2008
Something That Does Not Make Sense
Example 1: Anyone really been far even as decided to use even go want to do look more like?

Example 2:

10:22 PM - ¢a$h |Boozled|: my mate bought some game
10:22 PM - ¢a$h |Boozled|: and hes like
10:22 PM - Andiee: what
10:22 PM - Andiee: stop being sentry
10:22 PM - Andiee: and make sense
by Boozled August 8, 2009
Originating from Team Fortress 2, when the Engineer will shout "SENTRY DOWN!" if his sentry is destroyed.

Used on the internet to mean that the defenses are down; used jokingly in a flame war.
A: Umm...well... you're stupid!
by scy1192 April 29, 2008
Really fucking annoying bob-omb expies that run towards a Sentry and explode.
Alert! A sentry buster has entered the area!
Aw, hell.

by An Angry Engineer January 13, 2013
The spawn of Satan Himself. Even scunts and W+M1 pyros don't deserve to stare down the barrel of one of those horrors.
The much hated lime green tossle cap wearing scunt was hated by everyone because he was edgy, spammed ( ͡° ͜ʖ ͡°) binds in the chat, and reked everyone who tried to fight him, but even him didn't deserve to get mowed down by a mini sentry.
by TheHunterOfPussy October 29, 2017