energia

1. A general term referring to the "energy" or vigor of a expression. (Silva Rhetoricae)

2. 226. DEFINITION OF ENERGY.
The word energy is used by Dr. Whately in a very comprehensive sense, namely, as expressive of that vital element in style which is here called persuasiveness. Such an extension of its meaning is, however, liable to objection; first, because it has a definite signification of its own; and, secondly, because there are certain qualities belonging to this present division of style which cannot be classified under such a head. This word is generally explained by such terms as "force," "vigor," or "strength," and energy in style may, therefore, be defined as strength of expression. (De Mille)

3. ENERGY is that quality of style by the use of which thought is forcibly expressed. Perspicuity is essential to energy, since what is indistinct is not seen, and is not felt; imagery conduces to energy, as it presents the thought more graphically than plain language can do it: but energy, employing these grand qualities of style, is something different from them. A thought may be perfectly distinct, and may be expressed in a figure; but it may not concentrate upon itself one's whole attention, and powerfully affect him. (Kellog, 136)

2. A general example of this quality may be found in the following passage from Emerson:
"A foolish consistency is the hobgoblin of little minds, adored by little statesmen and philosophers and divines. With consistency a great soul has simply nothing to do. He may as well concern himself with his shadow on the wall. Out upon your guarded lips. Sew them up with packthread-do. Else, if you would be a man, speak what you think to·day in words as hard as cannon-balls, and to-morrow speak what to-morrow thinks, in words as hard again-though it contradict everything you said to-day. ' Ah, then,' exclaim the aged ladies, 'you shall be sure to be misunderstood.' Misunderstood! It is a right fool's word." (De Mille)