noun. informal. 1 A magazine (periodical) More example sentences. 'the bestselling rock mag in Britain'. 'Magazines, the new store on Church Street, offers foreign mags and back issues at unbelievable prices'. 'The glossy mags are bought and paid for - and, in some cases, owned by the media conglomerates who own the record companies. List Of 4 Surprising Name Meanings. M Letter M Meaning Of Mags Imaginative, intense, sensitive and hard working, those are all traits defining you if your name has a M in it. Once you get involved in a relationship you consistently spend a considerable amount of.