Translation guide
In Japanese, the word for 'hot water' depends on context: plain hot water, hot water for bathing, or boiling water. The most common everyday word is お湯.
The most common way to refer to hot water in daily life, such as for tea, instant noodles, or washing.
The standard, polite word for hot water. Used for drinking, cooking, washing, etc. The prefix お adds politeness; the plain form 湯 is less common in everyday speech.
Please boil some water.
I washed my hands with hot water.
The plain form of お湯. Used in compounds, signs, or casual contexts. Less polite on its own.
Please check the temperature of the hot water.
Specifically water that is at a rolling boil, often for cooking or making tea.
Water heated for a bath, typically in a bathtub or onsen.
The hot water in a bathtub. お風呂 means 'bath', so this specifies the water inside it.
The bath water has gone cold.
Similar to お風呂のお湯, but 湯船 specifically means 'bathtub'.
Please drain the bath water.
Hot spring water. Used when referring to the water from a natural hot spring.
The water of this hot spring is very soft.
Hot water as a utility in a building, like from a tap or water heater.
水 (みず) means cold water. Using it for hot water is incorrect. Always use お湯 or another appropriate term.
お湯 is the polite form and is used in most daily situations. Dropping the お (just 湯) can sound blunt or is used in compounds.
Pour boiling water into the cup noodles.