The title Elder is given to all men in the Melchizedek Priesthood. Even though they have weekly elder quorums, they don’t refer to each other as Elders. Instead, they call other men “brothers” and women “sisters.” Within the LDS Church, the only people who call themselves “elders” are missionaries and General Authorities. Although many Christians chafe at addressing young LDS missionaries as elders, it is good to do so. To insist on calling them their first names creates an unnecessary obstacle and introduces friction into the relationship.
Dictionary of "Mormonese"
Stop talking past each other. Gain a better understanding of the words that are unique to Mormonism and the differences of shared terms between Mormonism and Christianity.