Portmanteau of "cell" phone and "sulking"; someone who's getting all upset/butthurt that the person they're calling or texting isn't responding.
"Is Steve coming out tonight?"
"Nah, he's cellking cuz he's been blowing up Mandy's phone all damn day and she still ain't hit him back yet."
"Nah, he's cellking cuz he's been blowing up Mandy's phone all damn day and she still ain't hit him back yet."
by hunterbehunted May 8, 2015