单词	Allotheria
释义	Allotheria plural noun Al·​lo·​the·​ria : a subclass of Mammalia comprising small primitive forms extinct since the early Cenozoic, being usually considered coextensive with the Multituberculata but sometimes extended to include the Protodonta and Triconodonta Word History Etymology New Latin, from all- + -theria First Known Use 1880, in the meaning defined above
随便看	operancy operand operands operant operant conditioning operantly operants operas operatable operate operated operates operatic operatically operatics operating operating room operating system operating table operating theatre operation operational operational calculus operational fatigue operationalise

英语词典包含469781条英英释义在线翻译词条，基本涵盖了全部常用单词的英英翻译及用法，是英语学习的有利工具。