adverb
commonly called; popularly known as; in everyday language
Used to introduce a common or colloquial name for something, often contrasting with a formal or technical term.
この花は俗に「金魚草」と呼ばれている。
This flower is commonly called 'snapdragon'.
俗に言う「三日坊主」だね。
It's what people commonly call a 'three-day monk' (someone who gives up quickly).