Translation guide
The English verb 'hydrate' can refer to providing water or moisture to something, or to the chemical process of combining with water. This guide focuses on the everyday meaning of adding water to a person, body, or substance, and the chemical sense.
Expressing the action of drinking water or ensuring the body has enough water.
The most common and natural way to say 'to hydrate' in the sense of drinking water or taking in fluids. Literally 'to take moisture/water'.
暑い日はこまめに水分を取ってください。
Please hydrate frequently on hot days.
運動中はしっかり水分を取りましょう。
Let's hydrate properly during exercise.
A slightly more formal or technical phrase meaning 'to replenish fluids'. Often used in medical, sports, or instructional contexts.
脱水症状を防ぐために、定期的に水分補給をしてください。
To prevent dehydration, please hydrate regularly.
Simply 'to drink water'. This is the most direct and casual way to express hydrating by drinking water, but it only refers to water, not other fluids.
のどが渇いたから水を飲もう。
I'm thirsty, so let's hydrate (drink water).
Expressing the action of adding water to a substance, such as food, soil, or skin, to make it moist or restore its water content.
Transitive verb meaning 'to moisten' or 'to dampen'. Used for adding moisture to things like cloth, soil, or food.
乾燥した土を湿らせてから種をまきます。
Hydrate the dry soil before sowing seeds.
タオルを湿らせて顔を拭いた。
I moistened a towel and wiped my face.
Literally 'to give moisture'. A more general phrase that can be used for plants, skin, or other things that need water.
肌に水分を与える化粧水を使っています。
I use a lotion that hydrates the skin.
Used specifically for rehydrating dried foods like wakame or shiitake by soaking in water. Often used as 水で戻す.
Referring to the chemical process where a substance combines with water molecules.
The technical term for chemical hydration. Used in chemistry contexts.
セメントは水と反応して水和する。
Cement reacts with water and hydrates.
A more descriptive phrase meaning 'to combine with water'. Can be used in explanations.
この化合物は水と結合して水和物を作る。
This compound combines with water to form a hydrate.
The English loanword ハイドレート is rarely used in Japanese outside of very specific technical or product contexts (e.g., 'hydrate' in chemistry or some cosmetic product names). For everyday hydration, use the Japanese phrases above.
Rehydrate dried wakame in water before using it in cooking.