'un portable' may be a cellular phone / or / a portable computer
"pour moi un portable" means "for me a cell phone" (or a portable computer, as "portable" could mean both in French)
"un portable" may be a cellular phone (also called un téléphone portable, or un mobile) or a notebook computer.
This is a black cell phone / or / notebook computer
a cell -> une cellule a cell phone -> un téléphone portable, or simply un portable
un'' portable.
In French, mobile phone is: téléphone mobile.
a cellphone is called 'un téléphone portable', and most often 'un portable' in French.
The French word portable is masculine and may be used as follows: J'utilise un portable ("I use a notebook").
Phone is "téléphone" in French. A cell phone is most often called "un portable" (simplification of "un téléphone portable").
Literally, it would be "chaise d'ordinateur."
A DVD is relatively portable but I suspect you mean a DVD player? In which case it's only portable if it's a portable DVD player.
I hope you mean 'What do the initials 'UN' mean - United Nations.