point d'appui

From French point d’appui (“point of support”).

point d'appui (plural points d'appui)

1. (military) A given point or body upon which troops are formed, or by which they are marched in line or column.
   • 1795, Rules and Regulations for the Cavalry, Adjutant General's Office, page 364,

     Marched from the left, and to deployer to the left.—In which caſe the right squadron moves ſtreight forward to the point d'appui marked by the Quarter Maſter, &c. &c.

   • 1911, The Royal Engineers Journal, page 122:

     The attacking artillery, firing at a point d'appui at long range, cannot be said to be immobilized, because it has the power of diverting its fire to neighbouring points d'appui; […] .

2. (military) An advantageous defensive support; a foothold.
   • 1989, Daniel Berthold-Bond, Hegel's Grand Synthesis: A Study of Being, Thought, and History, State University of New York Press, page 40,

     Its intention and its method is to "stand back from natural objects, leaving them as they are and adjusting ourselves to them," and its point d'appui and point de depart is sense experience (PhN §246 Zusatz).

   • 2009, R. S. K. Barnes, Peter P. Calow, P. J. W. Olive, D. W. Golding, J. I. Spicer, The Invertebrates: A Synthesis, Wiley, page 252:

     If, on the other hand, the points d'appui are in regions of longitudinal muscle contraction so that the fixed body regions are at their shortest, the animal will move in the opposite direction to the wave, the wave is said to be retrograde.

3. (music) A specific note, chord, or phrase that serves as a stable reference point within a piece of music, providing harmonic or melodic grounding.
   • 1878, “Musical Association”, in The academy, volume 13, page 328:

     Any note belonging to these forms a point d'appui, which may be used mentally to pass to any note standing in a simple relation to the point d'appui.

   • 1879, Moritz Karasowski, Frederic Chopin: His Life, Letters, and Works, page 138:

     One thing, indeed, is frequently lacking in Chopin's compositions—especially in those written in the larger forms—the thematic work, which is the point d'appui in the works of Beethoven and the older masters.

   • 2013, Andrew Deruchie, The French Symphony at the Fin de Siècle, page 76:

     Whatever intrinsic melodic interest the theme may hold, its point d'appui, like the "faith" theme's, bears on the symphony's plot.

4. A focal point; a centre of attention.
   • 1871, Alonzo Calkins, Opium and the Opium-appetite, page 235:

     Get a point d'appui from which to make your approaches, bring out the key-note to which the strained heart-chords shall respond in harmonious echo, and the battle is half won.

   • 1891, Eclectic Magazine, and Monthly Edition of the Living Age, page 819:

     Here then was a point d'appui which appealed to the mind of the great worker in the world of the unseen.

   • 1948, J W Coomber, Making Men, page 176:

     A breaking up of the year, therefore, into periods with a point d'appui for each, is very necessary to throw an additional stimulus into the humdrum work of the boys.

5. An anchor point against which one pushes.
   • 1834, Baron Dupuytren, “Permanent Retractions of the Fingers, Produced by an Affection of the Palmar Fascia”, in The Lancet, volume 2, page 222:

     Thus the wine merchant and coachman of whom we shall presently speak were obliged, the one to perforate continually the casks with a gimlet, the other to ply his whip unceasingly on the backs of his jaded horses: it is also seen in masons who lift stones with the extremities of the fingers, in ploughmen, &c.; hence we see that the disease occurs most frequently in those who are forced in working to make the palm of the hand a point d'appui.

   • 1842, William Laxton, The Civil Engineer and Architect's Journal - Volume 5, page 299:

     The point d'appui of this lever is the pin to which it is attached; the moving power is the rower; and the resistance is the fluid; which is, however, contrary to the opinion of some writers.

   • 1897, Journal of the Society of Arts - Volume 45, page 151:

     The above points to the fact that all animals who have the power to lift, strike, or hug have the false cords fully developed, because, in order to get lifting power, force to strike, or to hug, the breath must be held in check: the thorax then forms the point d'appui, or point of resistance.