In Japanese, there are several words for "warm" and several words for "cold" and things can get confusing.
Here are some explanations:
1. Translations of "cold"
When speaking about the weather, about how you feel, you have to use the following word:
- It is cold today. 今日は寒いです。(kyou ha samui desu)
- Are you cold (do you feel cold) ? 寒いですか。(samui desu ka)
When speaking about objects, especially food and drinks, the correct word is:
- 冷たいサラダ (tsumetai salada): a cold salad (ie served cold)
If you were to use 寒いサラダ(samui salada), you would basically mean a salad which feels cold (needs a jacket ?).
2. Translations of "warm"
Things get even more confusing for "warm".
When speaking about the weather or about how you feel, you have to use the words:
暖かい/あたたかい/atatakai for warm (Japanese people often refer to it as "nice warm") and 暑い/あつい/atsui for hot (think about it as "too warm", "not-pleasant warm").
I noticed that in practice, when speaking about the weather, a foreigner will only use the term warm as the equivalent of "atsui". "atatakai" will simply be seen by foreigners as being a good weather "ii tenki ".
Also, please note that orally, "あたたかい/atatakai" is often reduced to "あったかい/attakai", especially in casual contexts.
When speaking about objects, again especially about food and drinks, the correct words are:
温かい/あたたかい/atatakai for warm and 熱い/あつい/atsui for hot.
You can notice that the pronunciation is the same as earlier, but the kanjis are different.
This time, it is generally easier to make the difference between "atatakai" and "atsui". "atatakai" simply means the dish/drink is supposed to be served warm, while "atsui" will imply it is really hot.
- 温かいサラダ (atatakai salada): a salad served warm (warm pieces of chicken ? melted cheese ?)
- スープが熱くて飲めなかった (su-pu ga atsukute nomenakatta): I can't drink this soup, it is too hot (notice: this is written in a familiar register, don't use it in polite situations).
- both 温かいお茶 (atatakai o cha) and 熱いお茶 (atsui o cha) are correct. I would personally rather use the first one.
3. When English is interfering
Recently, English has been interfering and you will hear more and more "hot" and "ice" instead of "atatakai" or "tsumetai" for drinks, in coffee shops for example. If you are not expecting it or are not used to Japanese pronunciation of English words, this may also confuse you ("hot" is pronounced "hotto", "ice" is generally pronounced correctly).
I hope this make things clearer to you, here are some final examples:
- 暑い時に、冷たいドリンクがいいね。 (atsui toki ni, tsumetai dorinku ga ii ne): when it is warm outside, it is good to get something cold to drink.
(notice again: this is casual Japanese)
- 温かい内に (atatakai uchi ni): "while it's hot", often used when telling other people to start eating and not wait for you / your meal, ... (in this context we would add the word どうぞ(douzo) at the end).
Also, Japanese people are too polite to correct you if you make a mistake, so you will have to be careful on your own. Don't stress too much about it though, it will come with time (you can come back here, if you forget which is which or which are the correct kanjis...).
Again, please feel free to ask questions, post a comment, share this post, facebook-like it, google +1 it...
PS: I just noticed another article about this topic:
(it is focusing on warm/hot but is more complete than this post)
PS2: You probably already have an electronic dictionary but if not, I recommend the Ex-word. I have one myself and got my brother one for his birthday and we are satisfied with them. Click on the picture to get it on Amazon: