The term 'BASIC INGREDIENT' can be summed up by two crossword solutions: STAPLE (6 letters) and TOBACCO (7 letters). STAPLE is a noun that refers to a food or other item that is regularly consumed or used. It is usually a basic ingredient in a diet or lifestyle. TOBACCO is a plant that is widely cultivated for its leaves, which are dried and fermented before being used in various products, including cigarettes, cigars, and snuff. It is also used as an ingredient in some medicines and as a flavoring agent in certain foods.