公元前738年，古罗马历法规定一年只有304天，一年只有10个月。古罗马大帝 朱利叶斯·凯撒 认为自己的名字很牛，于是根据自己的名字Julius搞出来一个变形的July单词，并命名为七月，并将它插入原来的月份中，于是10个月变成了11个月。在凯撒被刺死之后，其孙子屋大维（Octavian。 因其丰功伟绩被古罗马的元老院授予“奥古斯都 Augustus”称号），于是在其首封“奥古斯都”称号的月份叫做August(即来自奥古斯都的称号)为八月，原来的八月及其之后的月份往后移动，最终变为了12个月。
奥古斯都 在古罗马被认为“伟大、庄严”的意思。
英文的月份名称源自古罗马历法，有些按数字顺序排列，有些用神或皇帝命名。比如，“十月”October的拉丁语词根“octo”意思其实是“八”，八爪章鱼octopus也是这个词根。那为何月份跟实际数字会有错位呢？听韦氏词典编辑给你详解~
January
January is named after the Roman god Janus, who presided over doors and beginnings – appropriately enough, for the beginning of the year (though this is, as you will discover, not as straightforward as it seems). Indeed, Janus was usually depicted with two faces looking backwards and forwards, as is often characteristic of a new year.
在罗马传说中，有一位名叫雅努斯(Janus)的守护神，负责掌管所有的出入门户，象征开始。事实上，雅努斯生有两副面孔，可以同时看前也能看后，一副回顾过去，一副要眺望未来，所以人们认为选择他的名字作为除旧迎新的第一个月月名，很有意义。英语January，便是由这位守护神的名字演变而来的。
February
February is ultimately based on Latin februarius, from februa. In case that’s not helped things become clearer, februa was the name of a purification feast held on the 15th of this month.
February由拉丁文februarius演变而来，源于februa。Februa是本月第15天举行的一种宗教节日的名称。
March
Which god gets a planet and a month named after him? You’ve guessed it: Mars. Why him? As the Oxford English Dictionary notes, ‘In ancient Rome several festivals of Mars took place in March, presumably in preparation for the campaigning season, since Mars was a god of war.
这个月份的月名又是由哪位神灵的名字演变而来的？你们可能猜到了:战神玛尔斯(Mars)。据《牛津英语词典》记载，在古罗马，3月是每年出征远战的季节，为了纪念战神，人们便把他的名字作为3月的月名。
April
We know that the English word April comes from the Latin Aprillis, the fourth month of the ancient Roman calendar, but things are less clear after that. In Old English, April was also sometimes called Eastermonab, ‘Easter month’.
对于四月的由来较不明确，可能是从拉丁文Aprillis演变来的，是罗马旧历法的第四个月。在古英语中，April也被称为Eastermonab，即Easter month。
May
The month is connected with the goddess Maia. Perhaps less well known now than the other deities with months named after them, Maia (in Greek mythology) was daughter of Atlas and mother of Hermes. She was considered a nurturer and an earth goddess, which may explain the connection with this springtime month. Although may is a common modal verb, the month and the word are unrelated.
希腊神话中的女神迈亚(Maia)，是泰坦神阿特拉斯(Atlas) 的女儿，大神赫尔墨斯（Hermes）的母亲。专门执掌繁殖和生长的女神，在这春意盎然的季节，用她的名字来命名再合适不过。而单词may为情态动词，和月份名字没有关联。
June
Having conceded one month to a Greek deity, we’re now back with the Romans: June is named after the ancient Roman goddess Juno, wife of Jupiter and goddess of marriage and childbirth.
刚才介绍的是一位希腊女神，而六月则是根据罗马神话里神后朱诺（Juno）的名字演变而来的，朱诺是神王朱庇特（Jupiter）之妻，司管婚姻和生育的女神。
July
The first month in the calendar named after a real person, July was named in honour of Julius Caesar after his death in 44 BC, July being the month of his birth. Before it was renamed, the month was known as Quintilis (borrowed into English as Quintile), which means ‘fifth’. If you’ve been counting, you’ll know that July isn’t the fifth month: we’ll come on to that when we reach September and October.
这是第一个以真人名字命名的月份，罗马统治者朱里斯·凯撒（Julius Caesar）大帝被刺死后，著名的罗马将军马克·安东尼建议将凯撒大帝诞生的7月，用凯撒的名字——拉丁文Julius命名之。在重新命名之前，7月被称为Quintilis，在英语里就是Quintile，意为第五。很明显，七月并不是第五个月份，至于为什么会有这个名称，我们后面说到九月和十月时会作出解释。
August
Following suit, in 8 BC, the month Sextilis (‘sixth’) was renamed after Augustus, the first Roman emperor, who had died six years earlier. Augustus himself was given this title when he became emperor, having previously been known as Octavian. It came from the Latin augustus meaning ‘consecrated, venerable’ which gave rise to the English adjective august, ‘respected and impressive’.
如今八月的英文名字是根据古罗马帝国开国皇帝奥古斯都（Augustus）的名字命名的，在改名前称为Sextilis，意为“第六”。奥古斯都，原名屋大维（Octavian），他登基后获得了“奥古斯都Augustus”的尊号，取自拉丁文augustus，意为神圣、至尊的意思。而形容词august也相对有了令人敬畏、显赫的意思。
September
September follows on from Quinitlis and Sextilis, in that it comes from the Latin septem, ‘seven’. As with those (and the rest of the calendar), the numbering is a bit off now: September was originally the seventh month in an ancient Roman ten-month calendar, which started with March.
September源自拉丁文septem，就是“七”的意思。原来古罗马人只把一年分为十个月，March是一月，而September正好就是七月。
October
More of the same: octo is the Latin for ‘eight’, for that ten month calendar. Two months were added to the end of the calendar year around 713 BC, and the beginning of the year was moved to 1 January in 153 BC.
和上面说到的九月一样，英语中的十月，来自拉丁文octo，即“八”的意思，也是根据老历法来的。公元前713年，历法被修改，增加了两个月放在年尾，而到了公元前153年，才以1月1日作为新一年的开始。
November
The pattern continues: November comes from novem, ‘nine’.
英语中的十一月取自拉丁文novem，即“九”的意思。
December
And we finish off the year with December, from decem, ‘ten’.
英语中的十二月，来自拉丁文的decem，意为“十”。
正因为前面的July和August的插入，使原来的7月、8月、9月、10月，依次往后顺延了2个月，使其分别变为了9月、10月、11月、12月；
即：
9月的Sept词根本身表示7；
10月的Oct词根本身表示8；
11月的Nov词根本身表示9；
12月的Dec词根本身表示10，正因为前面有7月和8月用人名命名的先例，所以这里也是把自己的名称给变成了独立的月份；
