As a sociolinguist, Ishiguro studies the evolving meanings of words and the word choices we make day in and day out. From his perspective, the ultimate definition of yoroshiku onegaishimasu is this: to entrust yourself to the other person.

He believes that the phrase serves two types of requests: when entrusting yourself to another person or entrusting a task to another person. “In both cases, the underlying aim of the phrase is to establish or build a trustable relationship.”

The first way of using yoroshiku onegaishimasu is as a type of greeting either at the beginning or at the end of a relationship or a situation. You would use it if meeting someone for the first time, for instance, or when starting or ending a business meeting, or when parting with someone. Players of martial arts or shogi (a Japanese board game), for example, start their match by saying ‘yoroshiku onegaishimasu’ to the opponent to establish a relationship – for the duration of the match, at least.

The second type of yoroshiku onegaishimasu is used when you are asking someone to do a task for you, perhaps a favour. This would often be at work either in person or in emails.

Another way to request something in Japanese is to use kudasai (conjugated form of ‘kudasaru’ which means ‘to give’).

“The problem with kudasai is that it can be too direct and might come off as being rude. Yoroshiku onegaishimasu is a politer and more convenient alternative,” explains Ishiguro. “You are showing your complete trust in the other person to complete the task, leaving the relationship on a good note.”

That being said, the phrase isn’t a simple swap-out for the Japanese textbook version of ‘please’. It’s more nuanced than that – but the more you use it, the better you understand it.

“For me, I think of it as a way of saying ‘please’ when asking for something,” says David Corbin, the CEO of Tech in Asia Japan, a networking organisation for Japanese startups. He has lived in the country for over nine years. After years of working in Japan or with Japanese people, Corbin has come to learn that “in emails, you must include yoroshiku onegaishimasu at the end of the message, even if there is no specific request being made.” Iima agrees: “It is frequently used not for its literal meaning of requesting something, but for the purpose of showing respect and is a counterpart to with regards or best regards in English.”

Joji Fujinaga, an English teacher, remembers a Japanese student who translated yoroshiku onegaishimasu as ‘I will beg for your kindness.’ But “this is way too polite in spoken conversation, but I can see what the student was trying to convey.”

The main takeaway of the phrase, in terms of how it fits into Japanese culture? “In our society, in any given situation, the person you are talking to is more important than yourself.”

Ishiguro believes using this phrase “puts emphasis on ‘how’ (your attitude) it is being said rather than ‘what’ (your request) is being said”. In other words, how polite you are matters more than what you actually say.

This does not seem too crazy, considering the Japanese language has three types of conjugations alone for a form of the language called keigo (a respectful form of Japanese used for strangers, elders or in formal situations that is used on a daily basis).

“I found ‘looking forward to’ the best translation,” says Nils Valentin, a German expat currently living in Tokyo. “When you use it, you are already indirectly anticipating there might be some type of conflicts to be solved in future, or you simply need a helping hand, or it’s a polite way of implicitly saying, ‘Sorry for bothering you with this task, I know it’s a lot to ask, but please help me, I could really need your help right now.’”

In short? “The phrase is used very generally just to keep a good relationship with the people around you,” he says. “As such it can have so many meanings.”

Despite its complexity, perhaps the way this phrase is used is something we should all keep in mind to remind us of the indispensable role respect and trust plays in any good relationship. And that’s something people value – no matter how you say it.

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