letter

alphabet, letter, character, script

letter, note, correspondence, message

名词 letter:

1. a written message addressed to a person or organization
   同义词：missive
2. the conventional characters of the alphabet used to represent speech
   同义词：letter of the alphabet, alphabetic character
3. a strictly literal interpretation (as distinct from the intention)
4. an award earned by participation in a school sport
   同义词：varsity letter
5. owner who lets another person use something (housing usually) for hire

动词 letter:

1. win an athletic letter
2. set down or print with letters
3. mark letters on or mark with letters

1. There was nothing in the letter of particular importance.
   这封信里没有什么特别重要的事。
2. There are two collections a day from this letter box.
   这个邮箱每天开两次。
3. Put this letter in the main file.
   把这封信放在主要文件夹中。
4. Have you answered her letter?
   你给她回信了吗？
5. This word has five letters.
   这个单词有五个字母。

let.ter

n.（名词）
A written symbol or character representing a speech sound and being a component of an alphabet.
字母：一种书写符号或代表一个语音的特征，是字母表的组成部分
A written or printed communication directed to a person or an organization.
信：发给某人或某种组织的书写或打印的通讯
Often letters A certified document granting rights to its bearer.
常作 letters 许可证：证明持有者某些权力的证明文件
Literal meaning:
字面意思：
例句：
had to adhere to the letter of the law.
必须恪守法律的字面意思

letters (used with a sing. verb)
letters （与单数动词连用）
Literary culture; belles-lettres.
文学；纯文学
Learning or knowledge, especially of literature.
文学知识：尤指文学方面的学问或知识
Literature or writing as a profession.
文学家，作家
Printing
【印刷术】
A piece of type that prints a single character.
（一个）铅字：印刷某一个字的铅字
A specific style of type.
字形：铅字的某种特定印刷体例
The characters in one style of type.
铅字字体：铅字某种印刷体例中的字符
An emblem in the shape of the initial of a school awarded for outstanding performance, especially in varsity athletics.
校名字首形式的徽章：以学校名字首字母的形状制成的徽章，奖给那些表现优异的人，尤指那些大学体育竞赛中表现优异者
v.（动词）
let.tered,let.ter.ing,let.ters
v.tr.（及物动词）
To write letters on.
写上字
To write in letters.
以文字写上
v.intr.（不及物动词）
To write or form letters.
写字，造字
To earn a school letter, as for outstanding athletic achievement:
获得校名字母徽章：赢得学校名字母缩写徽章，如因取得体育竞赛优异成绩者：
例句：
She lettered in three collegiate sports.
她在三次大学生体育竞赛中获得校名字母徽章

<习惯用语>to the letter
To the last detail; exactly:
严格按照文字；精确地：
例句：
followed instructions to the letter.
不折不扣地遵照指示

来源：
Middle English
中古英语
from Old French lettre
源自 古法语 lettre
from Latin littera
源自 拉丁语 littera
perhaps from Etruscan
可能源自 伊特鲁里亚语
from Greek diphthera [hide, leather, writing surface]
源自 希腊语 diphthera [兽皮，皮革，书写表面]

【引伸】
let.terer
n.（名词）
<参考词汇><同义词>letter,epistle,missive,noteThe central meaning shared by these nouns is .a written communication directed to another.:
这些名词共有的中心意思是指.发给别人的一种书面交流形式.：
例句：
received a letter of complaint;
收到一封投拆信；

例句：
the Epistles of the New Testament;
新约圣经的使徒书信；

例句：
a missive of condolence;
慰问公函；

例句：
a thank-you note.
致谢信