# hydro

/ˈhaɪˌdɹoʊ/ (US) · /hˈaɪdɹəʊ/ (UK)

Source: https://englishreference.com/word/hydro
Updated: 2026-08-08

## Senses

### 1. electricity supply

noun · CEFR B2 · Dialect

the supply of electricity, or the bill you pay for it.

For teachers: the electrical power supply provided by a utility; by extension, the utility company itself or the associated billing.

- I need to pay the hydro before they cut off my lights.
- Residents in Ontario often complain about the rising cost of hydro during the peak summer months when air conditioning usage spikes.

### 2. hydroelectric power

noun · CEFR B2

electricity produced by the force of moving water.

For teachers: electrical energy generated through the use of falling or flowing water.

- The country gets most of its energy from hydro and wind power.
- The government invested heavily in hydro to reduce the nation's reliance on coal-fired power stations.

### 3. marijuana

noun · CEFR C1 · Slang

a type of marijuana grown in water rather than soil.

For teachers: cannabis cultivated using hydroponic methods rather than traditional soil-based agriculture.

- He was arrested for selling hydro out of his apartment.
- The police raid uncovered a sophisticated indoor operation dedicated to producing high-grade hydro for local distribution.

### 4. a spa

noun · CEFR C2 · British English · Archaic

a hotel or place where people go for health treatments using water.

For teachers: a hydropathic establishment or spa hotel providing therapeutic water treatments.

- The old Victorian hydro has been converted into a luxury apartment building.
- In the late nineteenth century, the town was famous for its hydro, attracting wealthy visitors seeking the water cure.

### 5. hydroelectric or hydroponic

adjective · CEFR B2 · Informal

related to water power or growing plants in water.

For teachers: relating to hydroelectricity or hydroponics; functions as a clipping in informal or technical shorthand.

- The farm uses a hydro system to grow lettuce all year round.
- The engineer reviewed the hydro project plans to ensure the dam could withstand seasonal flooding.

## Examples

- I need to pay the hydro bill before Friday.
- The province generates most of its energy from hydro, using several large dams located in the northern regions.
- Heavy rainfall during the autumn months significantly boosted the reservoir levels, allowing the utility to export surplus hydro to neighboring states at a premium price.

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