Mawson, C.O.S., ed. (1870–1938). Roget’s International Thesaurus. 1922.

Class I. Words Expressing Abstract Relations
Section VIII. Causation
3. Power in Operation

171. Energy.

   NOUN:ENERGY, physical energy, force; keenness &c. adj.; intensity, vigor, backbone [colloq.], vim [colloq.], mettle, vis viva [L.], vis vitœ [L.], pep [slang], ginger [slang], go [colloq.]; strength, elasticity; high pressure; fire; rush; human dynamo.
  ACTIVITY, agitation, effervescence; ferment, fermentation; ebullition, splutter, perturbation, stir, bustle; voluntary energy [See Activity]; quicksilver.
  EXERTION (effort) [See Exertion]; excitation (mental) [See Excitation]; resolution &c. (mental energy) [See Resolution].
  ACRIMONY, acridity, acritude [obs.]; causticity, virulence, poignancy; harshness &c. adj.; severity, edge, point; pungency [See Pungency].
  EXCITANT, stimulant; Spanish fly, cantharides; seasoning (condiment) [See Condiment].
   VERB:GIVE ENERGY &c. n.; energize, stimulate, kindle, excite, exert; activate, potentialize [rare], dynamize, doubleshot; sharpen, intensify; inflame &c. (render violent) [See Violence]; wind up (strengthen) [See Strength].
  strike, – into, – hard, – home; make an impression.
   ADJECTIVE:ENERGETIC, strong, forcible, active, strenuous, forceful, mettlesome, enterprising; go-ahead [colloq.]; intense, deep-dyed, severe, keen, vivid, sharp, acute, incisive, trenchant, brisk.
  rousing, irritating; poignant; virulent, caustic, corrosive, mordant, harsh, stringent; double-edged, double-shotted, double-distilled; drastic, escharotic; racy (pungent) [See Pungency]; excitant, excitative, excitatory.
  potent (powerful) [See Power]; radio-active.
   ADVERB:STRONGLY &c. adj.; fortiter in re [L.]; with telling effect.
  1. The steam is up.
  2. Vires acquirit eundo.
  3. The race by vigor not by vaunts is won.—Pope
  4. Like a steam-engine in trousers.—Sydney Smith—of Daniel Webster