COMBINE SUBSTANCES [I, T] › If two or more substances mix, they combine to make one substance, and if you mix two or more substances, you combine them to make one substance: Mix the powder with water to form a paste. Put the chocolate, butter, and egg in a bowl and mix them all together. Oil and water don't mix. COMBINE QUALITIES ETC [I, T] › to have or do two or more qualities, styles, activities, etc at the same time: a feeling of anger mixed with sadness MEET [I] › to meet and talk to people: She enjoys going to parties and mixing with people.