The crossword solution for the term 'PREFIX WITH MATTER' is 'ANTI'. The prefix 'ANTI' is derived from the Greek word 'ANTI', meaning 'AGAINST' or 'OPPOSITE'. It is commonly used to describe something that is opposed to or in opposition to something else. For example, an 'ANTI-war' movement is one that is AGAINST war. It can also be used to describe something that is the OPPOSITE of another thing, such as 'ANTI-gravity' which is the OPPOSITE of gravity.