What does "mutual" mean?

Mutual: Possessed, experienced, or done by two or more persons or things at the same time; common; joint; as, mutual happiness; a mutual effort. Burke. A vast accession of misery and woe from the mutual weeping, and wailing, and gnashing of teeth. Bentley. Note: This use of mutual as synonymous with common is inconsistent with the idea of interchange, or reciprocal relation, which properly belongs to it; but the word has been so used by many writers of high authority. The present tendency is toward a careful discrimination. Mutual, as Johnson will tell us, means something reciprocal, a giving and taking. How could people have mutual ancestors P. Harrison. Mutual insurance, agreement among a number of persons to insure each other against loss, as by fire, death, or accident. -- Mutual insurance company, one which does a business of insurance on the mutual principle, the policy holders sharing losses and profits pro rata.