The phrase "big picture" means considering the overall situation or understanding the main idea, rather than focusing on small details or specific parts. Full definition
Inside there will be a sparkly chandelier lit with candles hanging, pretty flowers landscaped around the outer sides, comfortable furniture and big pitcher of sweet tea. (thepurplepaintedlady.com)
You might be wondering how big this pitcher is and if it will fit in your fridge. (geekwrapped.com)