As per post, he isn’t just referring to the screen but to hardware design/engineering as well.
P.S don’t be that douche who has to go on and write a line long definition of a term. Do you break apart your every day words too? Yes that line has been termed as ‘retina’ or just think of it as ‘term abc’. Fucking get over it. It is always much easier and sane to use a designated term (be it pegged for marketing to begin with) than to write a 20 word sentence in middle of your sentence.