na-adjective, noun which may take the genitive case particle 'no', noun
inferior; low-grade; vulgar; lower-class
Describes something of low quality, rank, or social standing. Can be used for objects, ideas, or people, often with a negative or dismissive tone. The sense covers both objective inferiority and social class connotations.
この店の商品は下等な品ばかりだ。
The goods in this shop are all low-grade items.
彼は下等な言葉遣いをして、周囲を不快にさせた。
He used vulgar language and made those around him uncomfortable.