Synonyms for Axis:

n.

ally, convention, accession, the Geneva Convention, entente, accord, bilateral. curvature, horizontal, outline, line, diameter, inclined plane, chord, diagonal, arc. sunspot, corona, crater, magnitude. coordinate, design, block graph, bell curve, curve, diagram, chart, cross-section, bar graph. axis (noun)
bloc, axis of rotation, axis vertebra.
line (noun)
line.
middle (noun)
half-and-half, hub, bisection, midst, half, mean, pivot, midpoint, core, nucleus, epicenter, center, average, heart, nub, mediocrity, kernel, median, medium, halfway point, marrow, middle.
point around which something revolves (noun)
pivot, spindle, arbor, support, stem, axle, pole.
shaft (noun)
axle, spindle.

Other synonyms:

the Geneva Convention, bell curve, inclined plane, diameter, horizontal, bar graph, convention, diagonal, cross-section, sunspot, block graph, entente, diagram. accession, chord, magnitude, corona, ally, curvature. outline, arc, chart, coordinate. design, crater, curve. line. Other relevant words:
arbor, coordinate, support, spindle, curvature, design, magnitude, axis vertebra, sunspot, diagonal, curve, line, ally, bloc, dividing line, chord, axis of rotation, pole, stem, diagram, convention, axle, line of rotation, diameter, chart.

Usage examples for axis

  1. Night covered Europe and Africa, which would otherwise have been visible to me, and the shadow of darkness was steadily creeping across the Atlantic Ocean, as the Earth revolved upon its axis – Zarlah the Martian by R. Norman Grisewood
  2. It had been strange, indeed, that complete change of mental emphasis, that alteration of spiritual axis that had befallen him within the first weeks of his parliamentary life, nay, even before the Hurd agitation was over. – Marcella by Mrs. Humphry Ward