1 definition by kyle thinks of thisngs, I gues

Social Filter Deficiency

A syndrome in which the said subject has trouble deciphering which thoughts to express aloud, and which to keep silent.

Often the source of embarrassment of subject's companions.
One:
Kyle - Chad has SFD.
Bailey - You reckon so?
Kyle - Yes, he just asked me if I would graffiti the school's walls with him while we were eating thanksgiving dinner at my grandma's house!
Bailey - Yeah... he does have difficulty gauging what to and not to say.

Two:
Chad - (rather loudly) GUYS I'M SO DRUNK!!!
Krystan - Chad! Stop being to SFD! I'm on the phone with my mother!!

Three:
Chad - I really need to take a shit.
Teacher - ... SFD...
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