Useful Japanese phrases (that are difficult to translate)

There are some useful, commonly-heard Japanese words and phrases for which there is no perfect English equivalent. When I was in Japan, and talking to Japanese people in English, I used a lot of these words because they were culturally appropriate, or because they expressed my meaning more accurately than English could. (Or just because they're fun to say. ^_^)

itadakimasu! This is something Japanese people say right before eating a meal. In subtitles, it's often translated as 'bon appetit!' I don't know if it can really be translated. Maybe a combination of 'thanks for the food', 'I'm going to start eating now', etc.
Have you heard of 'keigo'? 'Keigo' is especially polite Japanese. When speaking very politely - for example, to a customer - Japanese speak differently and even use some different verbs. 'itadakimasu' is a polite, humble way of saying receive, accept, take, eat, drink, etc. So it's literally saying 'I (humbly) accept this food'. Although it sounds very polite, it's common, everyday Japanese and you can use it when eating out casually with friends too.

gochisousama (or more politely, gochisousama deshita) Just as you say 'itadakimasu' when starting a meal, you can say 'gochisousama deshita' after finishing. It literally means 'it was a feast!' but you can use it to mean a combination of 'that was great', 'thanks for the meal', 'I'm finished', etc.

irasshaimase! is the common greeting in shops. It means 'welcome'. You will hear this all the time from shop and restaurant staff. You don't have to reply to it. The verb 'irasshaimasu' is another keigo (very polite) verb meaning 'come, go, be'. So I guess it means 'come in' or something, in a very polite way.

osaki ni (or more politely, osaki ni shitsurei shimasu) You can say this if you do something before someone else. For example, if you are the first person to start eating something, or if you leave before someone else, you can say this as a way of excusing your bad behaviour. ^_^ 'Osaki ni' literally means 'before', and 'shitsurei shimasu' is like 'I'm rude' or 'please excuse me'.

ojama shimasu! 'Ojama' means something like 'intrusion' or 'nuisance'. You can say this when you enter somebody else's house. Even if they're your friend and they invited you, you can say this as you walk in, like 'oh, sorry to intrude'. Basically doesn't mean much beyond 'I'm coming in now!'

otsukaresama (or more politely, otsukaresama desu or otsukaresama deshita) Co-workers often say this to each other. It can be said at the end of a working day, or after a big effort/project at something, or just as a general sort of greeting throughout the day. It means something like 'we're/you're working hard', 'you must be tired', 'you've worked hard', 'we're working hard', 'keep up the good work'. It's a nice, and simple way, to acknowledge someone else's work and effort. 'tsukare' means 'tired', and the 'o' and 'sama' make it more polite. This is a polite way to acknowledge someone else's tiredness. I learned this expression quickly, as in the department store where I worked, any time any staff member met another in the corridor or elevator, they'd greet each other with 'otsukaresama desu!'

shou ga nai (or shikata ga nai) This expression means something like 'it can't be helped', 'we can't do anything about it' or 'oh well'. It indicates a sort of resignation and acceptance of a situation. Some people say this is a fairly typical attitude of Japanese in the workplace; a lot of people shoulder overtime or unfair work pressure with a 'shou ga nai' attitude, instead of complaining or fighting for their rights. A fair assessment? I don't know, but some companies do seem to assume their employees will take such an attitude.

genki This word can be translated to mean 'cheerful', 'happy', 'healthy', 'energetic', etc. If you ask someone 'genki desu ka?', you're asking if they're well. But because 'genki' encapsulates several different ideas, there's no perfect English equivalent. You can use it to describe someone who is perky and bubbly, or a child who is running around screaming, or a person who is healthy, or students who are actively participating in something...

mendokusai This is often translated by dictionaries as 'troublesome'. I usually translate it as 'it's a pain'. If something is a 'mendokusai', it's annoying or tedious to do, a pain, a disagreeable duty.

mottainai This means something like 'wasteful', but seems to be used to mean 'waste not, want not'.

sasuga This means 'what you'd expect'. For example, if your friend, who is very smart, gets the highest score in the class, you could say 'sasuga!' ('that's typical of you' or 'that'd be right') to show you are not surprised!

toriaezu This means 'at first' or 'to begin with'. It's often used in ordering, as in 'toriaezu, nama bi-ru' (for now, draft beer).

yoroshiku onegaishimasu A big one! This is a kind of greeting that people use a lot, especially at the beginning of a new relationship. For example, if you're a new employee, you will say this to people you meet, and they'll say it back to you. If you're a new student at a school, if you have to stand up in front of the class and introduce yourself, you'll say this. If you start a project and you need to ask people to work with you on it, you'll say this.

We really have no English equivalent; in these situations we'd just say 'nice to meet you', 'I look forward to working with you', 'I look forward to meeting all of you', 'I hope for your cooperation', etc. 'Yoroshiku' literally means 'well' or 'properly', and 'onegaishimasu' means 'please'.  It really means something like 'please treat me well' or 'let's work happily together' or 'let's have a good relationship'.

You can say it more casually as simply 'yoroshiku', and this can also mean something like 'best regards'.