In-common is a term used to describe something that two or more people, groups, or things have in common. It is often used to refer to SHARED characteristics, experiences, interests, or goals. For example, two people may have in-common a love of music, or two countries may have in-common a SHARED border. The term can also be used to describe a SHARED resource or responsibility. In this context, it is often used to refer to the collective responsibility of a group of people or organizations to work together to achieve a common goal.