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.
He used vulgar language and made those around him uncomfortable.
Even lower animals like amoebas have their own distinct ecology.
He hated being looked down on as an inferior person.
I wish you'd stop talking about such vulgar interests.