Twins fraternal异卵双胎﹔异卵孪生
Fraternal polyandry兄弟共妻;一妻多夫制
brotherly fraternal兄弟的;前者是低层次词汇
fraternal sentiments兄弟情
fraternal company互助公司
fraternal cell兄弟晶胞
fraternal unit兄弟单位
Fraternal greetings休息的权利
ADJ（形容词） Fraternal actions show strong links of friendship between two people or groups of people. 兄弟般的 [正式][usu ADJ n]
...the fraternal assistance of our colleagues and comrades.
...我们同事和伙伴间兄弟般的帮助。
ADJ（形容词） Fraternal twins are twins born from two eggs, so they are not exactly the same. They look different from each other and may be different sexes. 异卵双生的 [usu ADJ n]