[{"Bold_text": "noun", "List Items": ["the essential substance or details of a matter; basics; crux:Let's the chitchat and get down to the nitty-gritty."]}, {"Bold_text": "adjective", "List Items": ["fundamental, detailed, or probing:nitty-gritty questions.", "direct and practical:nitty-gritty advice; a nitty-gritty system."]}]