Stands for "fecal management system" in the hospital. It is a tube stuck up the anus of someone in the hospital if they are not capable of asking for a bedpan when they need. Used as something derogatory to call a person you don't like by hospital workers.
"I hate that bitch, she is such a FMS."
by SamanthaEmily February 28, 2008
Get the FMSmug. 'Fraid of Missin' Sumthin'
A condition where one is always on the lookout for the next cool thing, rather than enjoying what one has, because he/she is "afraid of missing something."
A condition where one is always on the lookout for the next cool thing, rather than enjoying what one has, because he/she is "afraid of missing something."
Ralph has a serious case of FMS. He's keeps scanning the joint. He can't just chill and have a good time.
by artbabe February 5, 2008
Get the FMSmug. by O-Lin-Lin April 18, 2021
Get the FMSmug. 
Get the FMmug. by VodkanLemons July 23, 2005
Get the fmmug. No, it does not mean fuck me sideways. Nor does it mean fuck my school. It stands for Flight Management System. It’s what the pilots use to calculate weight and balance, performa- wait shit people did you really fucking define this as “fuck me sideways”? really? who says this? whoever wrote that, if you’re on my flight, i’m kicking you off and plugging one less passenger into the FMS.
“hey captain, i think we gotta do a max performance takeoff today still. what’s the FMS saying?”
“oh sorry, i was fucking a girl sideways, what were you saying?”
“oh sorry, i was fucking a girl sideways, what were you saying?”
by Slappdat October 1, 2019
Get the FMSmug.