The term 'Mild Acid' can be defined by the crossword solution 'ACETIC', which is a 6-letter word. ACETIC acid, also known as ethanoic acid, is an organic compound with the chemical formula CH3COOH. It is a weak acid, meaning it has a low concentration of hydrogen ions when dissolved in water. ACETIC acid is found naturally in vinegar and is used in many industrial processes, such as food production and pharmaceutical manufacturing.