A mutual organization.

A form of insurance scheme owned entirely by its policyholders.

plural of mutual inductance

Two people who count each other as friends / plural of mutual friend

Someone who is a friend of two or more people, each of whom may not know each other.

(biology, sociology) The state of cooperation, as opposed to competition, as a factor in evolution and social development.

(law) An incident of multiple assaults and batteries on all sides between involved parties which does not rise to the level of felonious assault or battery, or serious bodily harm, where parties involved are determined to have voluntarily entered into the affray and hence no criminal charges result, in relation to the assaults and batteries.

(politics, public policy, military) The threat of massive retaliation using nuclear weapons should a potential enemy use them first, both sides being annihilated in the event of war.

(idiomatic, derogatory) A group of two or more people, in a workplace or other social environment, who routinely express considerable esteem and support for one another, sometimes to the point of exaggeration or pretense.

A financial institution chartered by a central or regional government, without capital stock, that is nominally owned by its members, who subscribe to a common fund.