I found this from the blog everynothing (though his use of it seems not to fit his defintion):
I recently sent a text message to my friend that read "I was tryna cop some jont and my man cised me. You tryna chill for a minute?" He responded "Dank dank." This conversation never actually happened, but it totally could have. I have realized that my friends and I converse in a language all our own. It is not like a sneaky drug code. That conversation could have been about anything from pot to sandwiches. When I write I avoid using this crazy vernacular, but I'd like to take a moment here to introduce and maybe analyze the etymology of the way we speak.
Tryna- Literally means trying to. It could be sexual (are you tryna with that girl?) or platonic (I'mma go to six flags. You tryna?)
Jont- Pretty much any noun. It literally could mean anything. (Lemme see that jont. I'm tryna get some jont. Where's my jont?) Jont is a strange mutation of the word joint I think. (also Jank Jams Janx-A-lanx Jiggidy-Jont Jontpiece)
Finna- Literally fixing to, it's like tryna but it can't stand alone. You can say I'm tryna but not I'm finna unless finna has an object
Cise - To give (Cise me that jont) I can't even explain where that came from. . .
Did some more sleuthing and may have narrowed it down some. I noticed the adjective cised listed at Urban Dictionary (UD) as well. Among other explanations of it being slang for "overjoyed" was this:
a word used entirely too much by the 99.1 WHFS Sports Junkies (Radio DJ's in DC)
Since this matches the geography found so far on cise, and since UD's entries on cised predate its entries on cise, I think it's safe to assume that the verb to cise came from the earlier adjective cised.
Following the Sports Junkies lead, I found cised used 136 times on their official website and cise used twice. I then found their official definition of cised, complete with pronunciation guide, on their Facebook page :
To be excited; (occasionally) sexually aroused. If used in a phrase such as "cised for [something]," it can simply mean that the speaker likes the thing in question. The word is pronounced with a soft "s" (as in 'side' or 'psychology') and rhymes with "iced", rather than with "excised" or "prized." This term is commonly preceded by the word “butt-” which may amplify the phrase to mean extremely excited.
UD users attribute the Sports Junkies with coining and popularizing several other slang words and phrases including grasper, work your trick, money metal, Lou Holtz and hogsmoke. Given this, and the popularity this show had in the D.C. Metro area, I'll put my money on the Junkies as original disseminators, and possible coiners, of the word.