The term 'primordial stuff' can be defined as the earliest form of matter, and the crossword solution for this term is 'OOZE'. Oozes are viscous liquids that are composed of a mixture of organic and inorganic materials, such as water, minerals, and organic compounds. Oozes are often found in areas with high levels of organic matter, such as swamps and wetlands. Oozes are also found in the ocean, where they are formed by the decomposition of organic matter. Oozes are important components of the Earth's ecosystems, as they provide nutrients to plants and animals.