单词	focal ratio
释义	focal ratio noun : f-number Example Sentences Recent Examples on the Web An eyepiece changes the focal ratio of your telescope, thus changing the magnification. Cameron Johnson, Popular Mechanics, 10 Nov. 2020 Word History First Known Use 1883, in the meaning defined above
随便看	fidley fido fidos fids fiducia fiduciae fiducial fiducially fiduciaries fiduciarily fiduciary fiduciary bond fiduciary coemption fiduciary contract fiduciary heir fiduciary relation fidus Achates fie Fiedler fiedlerite fief fiefdom fiefdoms fiefs field

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。