1. (n.) Internal or inherent power; capacity of acting, operating, or producing an effect, whether exerted or not; as, men possessing energies may suffer them to lie inactive.

2. (n.) Power efficiently and forcibly exerted; vigorous or effectual operation; as, the energy of a magistrate.

3. (n.) Strength of expression; force of utterance; power to impress the mind and arouse the feelings; life; spirit; -- said of speech, language, words, style; as, a style full of energy.

4. (n.) Capacity for performing work.

activity amperage animation application ardor armipotence assiduity assiduousness authority beef birr black power breeziness briskness brute force bubbliness charge charisma clout cogence cogency compulsion concentration dash decisiveness determination diligence dint drive duress dynamism ebullience effect effectiveness effectuality effervescence efficacy effort elan elbow grease endeavor endurance energeticalness exertion fervor flower power force force majeure forcefulness fortitude full blast full force get-up-and-go go guts gutsiness hard pull hardihood hardiness heartiness indefatigability industriousness industry influence intensity intestinal fortitude laboriousness life liveliness long pull lustihood lustiness main force main strength mana might might and main mightiness moxie muscle muscle power nerve and sinew obstinacy pains pep peppiness piss and vinegar pizzazz poop potence potency potentiality power power pack power structure power struggle powerfulness prepotency productiveness productivity puissance pull punch push relentlessness robustness ruggedness sedulity sedulousness sinew spirit spiritedness sprightliness stalwartness stamina staying power steam sticking power stoutness strength strength of will strenuousness strong arm sturdiness superiority superpower tirelessness toughness trouble tuck unsparingness validity vehemence verve vigor vigorousness vim virility virtue virulence vitality vivaciousness vivacity wattage weight zealousness zing zip