Uptight in an utterly
conceited sort of way.
Someone who 'acts' as if they are completely
superior towards/around another person.
Someone who's of the perception that they are 'better' (physically and mentally) than another.
"Me and Jen went to Saks the other
day, she's a completely different person over there, actin all sadiddy"
"Yo, if you wanna roll and
chill tonight we can do it, but don't try to be actin' all sadiddy around my homies"
"I am not goin' to the club with HIM","
Stop bein sadiddy and lez' go."