雨 pronunciations

Question

I have a question about this character: 雨

I know each kanji has so many pronunciations, this is pronounced "ame" but it has other pronunciations, could you please tell me when to pronounce it "ame", when to pronounce it "ama" and when "u".

Answer 1

At its core, the difference is that う is the 音読み, and thus is used in 漢語【かんご】 (words of Chinese origin). あめ and its related forms are 訓読み, and are used in combination with other readings of Japanese origin.

Now to get into some specifics...

Using あま

あま is related to あめ, and is used when あめ appears at the front of a compound and a vowel shift is required. For example:

• 雨燕【あまつばめ】 a type of bird
• 雨漏り【あまもり】 a leak
• 雨水【あまみず】

さめ as in 小雨【こさめ】 is another sound shift-based derivative, this time for when it appears at the end of a compound.

あま is also a reading for 天 (which has to do with the sky in this case), however this is in fact distinct from 雨 in nearly all cases. A review of matched pairings in 大辞林 produced just three such cases, each of which is close-but-not-quite:

• 天雲・雨雲 - technically it's くも for the first and ぐも for the second, but the dictionary indicates they are near-synonymous words for "the clouds in the sky". The distinguishing factor being that in the case of 雨 they naturally appear like they could start to rain any time.
• 天衣・雨衣 - both あまごろも. 天 indicates what a heavenly being would wear, while 雨 indicates rain gear.
• 天彦・雨彦 - both あまびこ. 天 indicates an echo, 雨 is a name from classical poetry

Using う

う is the Chinese-derived reading, and as such is used in 漢語. The 大辞林 entry on 雨【う】 provides several meanings and example uses:

Rain

• 雨滴【うてき】 raindrop
• 雨天【うてん】 rainy weather
• 雨量【うりょう】 rainfall; amount of precipitation
• 降雨【こうう】 rain; rainfall
• 慈雨【じう】 a welcome rain
• 驟雨【しゆうう】 a sudden shower
• 雷雨【らいう】 a thunderstorm
• 霖雨【りんう】 a rain that continues for several days

Examples of happiness or blessings

• 雨露【うろ】 great blessings (c.f. a country that benefits from the rain and dew). あめつゆ lacks the poeticism, and is simply "rain and dew".
• 慈雨【じう】 see above

Examples of things that fall like rain

• 弾雨【だんう】 a rain of bullets

In short, poetic usages seem to consistently fall under う. Beyond that あめ or one of its derivatives is your safest starting point when guessing on an unknown compound.