電気（でんき、denki）
- electricity/light

The Japanese word 電気 (pronounced でんき, *denki*) primarily means "electricity" or "electric power." It refers to the flow of electrical current, as well as the energy derived from that flow. It can also refer to electrical appliances or devices.

⚫︎ 電気を使う。 Translation: To use electricity. ⚫︎ 電気のコードが切れた。 Translation: The electrical cord broke. ⚫︎ この部屋には電気がない。 Translation: There's no electricity in this room.

You use 電気 when talking about: ⚫︎ The source of power for appliances. ⚫︎ The presence or absence of electricity. ⚫︎ Electrical systems and devices. ⚫︎ Phenomena related to the flow of electrons. You can use 電気 in both formal and informal contexts.

⚫︎ Kanji: 電気 ⚫︎ Hiragana: でんき (used when the kanji is not known or for emphasis) ⚫︎ Katakana: Usually not used, but you might see it in loan words related to electricity (e.g., in advertisements). ⚫︎ The okurigana (送りがな) is fixed; there are no variations.

⚫︎ There aren't many direct synonyms for "electricity." However, words that relate to the *effects* or *usage* of electricity could be considered similar in context. For example: ⚫︎ 電力 (*denryoku*): Electric power (usually referring to the amount of power).

⚫︎ There is no direct antonym. However, "lack of electricity" could be described by phrases such as: ⚫︎ 停電 (*teiden*): Power outage / Blackout.

最近、家の電気代が高いです。 ・Translation: The electricity bill at home has been high recently. ・Explanation: This sentence uses 電気代 (*denkidai*), a compound word meaning "electricity bill."

この機械は電気で動きます。 ・Translation: This machine runs on electricity. ・Explanation: This example explains the power source for the machine.

The word 電気 is a compound word: 電 (*den*) means "electricity" or "lightning," and 気 (*ki*) means "energy," "spirit," or "atmosphere." The combination reflects the understanding of electricity as a form of invisible energy or force. The use of this word originated from Chinese, where 電 and 気 are combined to mean electric power as well.