This article introduces a variety of interesting Japanese idioms that contain number(s)!
* In the following list, relevant 四字熟語 (よじじゅくご; idioms composed of four kanji characters) are introduced first, followed by the other idiomatic expressions.
一石二鳥 literally means “one stone two birds”, and it is a translation of the old English phrase, “kill two birds with one stone”, meaning “to succeed in achieving two things with a single action”.
Having a dog can make you feel relaxed and also help prevent crime; that’s “kill two birds with one stone”.
五十歩百歩 literally means ‘50 steps, 100 steps’. Figuratively, it means that there isn’t much difference among multiple choices. Usually, it contains a negative sense that none of the choices is great or appealing, and they look essentially the same, (e.g.) 20 minutes late vs. 30 minutes late.
This idiom originates from “孟子(Mencius), a classic Chinese text based on conversations and anecdotes of the Chinese philosopher Mencius. In one of the stories, Mencius made an analogy to fighting, which this idiom pertains to: in the battlefield, one soldier fled 50 steps from the battlefront, and another soldier fled 100 steps, and the former laughed at the latter for being a coward. Essentially, however, both of them did flee from the battlefield, and there isn’t much difference between them.
A: どの大統領(だいとうりょう)候補 (こうほ) が一番(いちばん)いいと思う？
A: Which presidential candidate do you think is the best?
B: 正直 (しょうじき)、どれも五十歩百歩でしょ
B: To be honest, they are pretty much the same (none of them is great).
十人十色 literally means “10 persons, 10 colours”. Figuratively, it means that everyone has a different personality, thought, life, etc. Its synonym is “人(ひと)それぞれ”, meaning “people vary” or “there are various people”.
理想的 (りそうてき)な仕事環境 (しごとかんきょう)は、十人十色だ
The ideal work environment is different for everyone (= Everyone has a different preference for their work environment).
一喜一憂 literally means “one joy, one grief”. Figuratively, it means that you are unduly and overly delighted or depressed by the situation. In other words, it means that you ride an emotional rollercoaster and overreact to even trivial matters. For instance, if you always feel elated when you get a text from your crush, and then suddenly feel dejected after you don’t receive a reply for 15 mins, you are doing “一喜一憂” pretty much.
It’s not great to feel overly delighted or depressed every day by the number of new infections of coronavirus.
嘘八百 literally means ‘800 lies’, and figuratively means “full of lies/sh*t”. Although being an advanced idiom itself, it has a very casual tone and can be used in a daily conversation.
あのブログの内容 (ないよう) は嘘八百だ
The content of the blog is full of lies/sh*t.
一か八か literally means ‘1 or 8’. It is used when you take a bold risk, wishing good luck. Its tone is similar to “go for broke”, like pushing yourself to make an action/decision without being certain of the success. (e.g) aiming at a last-minute goal from a long distance in a football match.
About its origin, one of the theories says that this idiom comes from a Japanese gambling game called 丁半 (ちょうはん), where you roll two dice and guess whether the total sum of numbers is even (丁; ちょう) or odd (半; はん). By taking a closer look at the two kanji characters, you can see that “丁” contains “一” (one) and “半” contains “八 ” (eight) turned upside-down on its top.
Taking a bold risk/going for broke, I confessed my feelings to her and got rejected.
バスケットの試合（しあい）で (In a basketball game)
Taking a bold risk/going for broke, I took a 3-point shot.
（ひゃくがい あって いちり なし）
百害あって一利なし literally means ‘(There are) 100 harms and no benefit’. Figuratively, it describes something negative that brings a lot of harms and no benefit, such as drugs, excessive drinking, and watching YouTube overnight. This expression is often used by anti-smoking people to describe the harms of cigarettes.
A lot of people say, “Tobacco brings 100 harms and no benefit”
Overly spoiling your children brings 100 harms and no benefit.