The word that a PC Wintel-using HTML programming geek uses to try and disguise his sloppy non-cross-platform programming skills. Usually said with an air of indignance. Example: Um, well, no - that table won't look right to you - it's a Mac-thing. Now, if you look at it on my PC...
MAC-THING
Meaning of MAC-THING in English
Slang English vocab. Английский сленговый словарь. 2012