精力|せいりょくseiryoku[1]atamadaka (head-high)

1. nounenergy; vigor; vigour; vitality
   彼女かのじょはその仕事しごとに精力せいりょくを傾かたむけた。↗

   She addressed herself to the task.

• SynonymバイタリティNeutralLoanword for exuberant vitality and drive; often used to praise someone as 「バイタリティがある」. Unlike 「精力」, it has no sexual-capacity sense.
• Synonym活力かつりょくNeutralThe driving force behind activity; also used of cities and economies, as in 「経済の活力」. 「精力」 is mostly about a person's physical and mental energy.
• SynonymエネルギーNeutralLoanword covering energy and power sources as well as personal drive; very broad in scope, including physical energy.
• Synonym気力きりょくNeutralMental strength to see things through; stresses willpower, while 「精力」 stresses abundant physical and mental energy.
• SynonymエナジーNeutralLoanword for energy, mostly in drink and product names such as 「エナジードリンク」.
• SynonymスタミナNeutralLoanword for stamina and endurance; also describes dishes that build you up, as in 「スタミナ料理」.
• Synonym力ちからNeutralStrength and ability; the broadest word of all. 「精力」 specifically means vigorous energy.
• Synonym生気せいきNeutralVitality or life in someone's look, as in 「生気がない顔」; focuses on facial expression and demeanor.
• Synonym精気せいきWrittenWritten/formal prose term for the vital essence or life force of a living being, with an Eastern health-cultivation flavor.
• Synonym活動力かつどうりょくNeutralThe ability to be active and take action; a written/formal prose word that is not used much.
• Related精せいNeutralSingle character for energy and spirit, seen mainly in set phrases like 「精を出す」 and 「精が出る」.
• Related元気げんきNeutralHealth and liveliness; the most common everyday word. 「精力」 is about the energy you can pour into work or a career.
• Related意気いきNeutralEnterprising spirit and drive, seen mainly in 「意気込み」 and 「意気揚々」.
• Related気勢きせいNeutralSurging momentum, usually as 「気勢を上げる」; focuses on the momentum of a group.
• Related根気こんきNeutralPatience and perseverance, as in 「根気強い」; stresses sticking with something without giving up.
• Related力ちからNeutralStrength and ability; the broadest word of all. 「精力」 specifically means vigorous energy.
• Related活気かっきNeutralThe liveliness of a place or atmosphere, as in 「活気のある町」; not used of a person's physical energy.
• RelatedタフネスNeutralLoanword for toughness, the strength to withstand pressure; stresses the capacity to endure.
• Related血気けっきNeutralThe hot blood and impetuosity of youth, seen in 「血気盛ん」; carries a hint of recklessness.
• Related精根せいこんNeutralEnergy plus perseverance, seen mainly in 「精根尽きる」; focuses on having used up all one's strength.
• Antonym無気力むきりょくNeutralAntonym: listlessness and lack of drive; the opposite of being full of energy.
• Antonym衰弱すいじゃくNeutralAntonym: physical weakness and decline; the opposite of being full of vigor.

Use 「精力」 for the vigorous physical and mental energy put into work or a career, as in 「精力的に働く」. In everyday talk say 「元気」; for endurance say 「スタミナ」; for willpower say 「気力」. 「活力」 extends to cities and economies, 「エネルギー」 to physical energy and power sources, and 「バイタリティ」 praises exuberant drive. The antonyms are 「無気力」 and 「衰弱」.

Usage comparisons are AI-assisted and cross-checked by multiple models; for study reference only

1. 物事ものごとを成し遂なしとげる活力かつりょく。
2. 性的せいてきな能力のうりょく。