Oikish means like an oik: loud, rough, and not well-mannered, in that same British, looking-down sense. You might call a laugh, a joke, or a way of talking oikish. The short dictionary line makes it sound like a person; though actually this form is the describing word, not the person-word (that is oik). It is informal, unkind, and rather old-fashioned. It describes manners, not a scientific fact and not a school label.

粗俗沒教養樣的（從 oik 來，同樣帶看不起人的英式味道）