na-adjective, noun which may take the genitive case particle 'no'
ordinary; typical; conventional; average
Describes something that is at the same level as most people or society in general, especially regarding lifestyle, behavior, or opinions. Often used in comparisons or to express conformity.
彼の給料は世間並みだ。
His salary is about average.
世間並みの生活ができれば十
I'm satisfied as long as I can live an ordinary life.
Compound of 世間 (seken, 'society, the world') and 並み (nami, 'average, ordinary'). The reading せけんなみ reflects a common rendaku-like voicing of なみ.