Abbreviation of "deskmate", which means someone who shares a desk with you. It can also mean someone who sits at the desk adjacent to yours.
I used to sit next to Carrie in high school—she was my deskie.
Deski is a badboy and a goodboy at the same time. he plays with girls’ heart with carefully for a reason; he doesn’t let the other one know what he does
Deski, Desky, Deskii