axis;  shaft;  center;  centre;  stalk;  stem
 time axis;  time basis;  timeline
 main spindle;  main shaft;  linchpin;  pivot;  principal axis;  main axis
 pivot foot;  emphasis;  priority;  focus
 axle;  pivot;  center (of power, activity);  central point;  the Axis (WWII alliance)
 innovation;  new departure;  milestone;  breakthrough
 basis;  foundation;  core;  criterion;  standard
 vertical axis;  vertical line;  vertical shaft;  spindle;  connection between past and present
 axis;  pivot;  central figure;  key man
 abscissa;  horizontal axis;  horizontal scroll
 Axis powers (World War II)
 point at issue;  axis of a conflict;  focus of confrontation
 (center portion of a) scroll (centre)
 Axis of Evil (Iran, Iraq and North Korea)
 bearing;  shaft bearing;  axle bearing;  plummer block;  pillow block
 axis;  axle;  plan;  contrivance
 same axle;  coaxial (cable)
 bearing;  shaft bearing;  axle bearing;  plummer block;  pillow block
 to focus on particular aspects of things
 matchwood;  splint;  stick;  scroll roller
 to rain heavily;  to be raining cats and dogs
 optical axis (of a lens, spherical mirror, etc.);  optic axis (of a crystal)
 axial flow;  axial current
 cultivar of Japanese apricot (Prunus mume);  cultivar of mulberry
 geometrical axis (of the eye)
 axis of symmetry;  line of symmetry
 triaxial compression test
 triaxial compression apparatus
 unconfined compression test
 unconfined compression strength
 shaft end;  axial end;  end of the shaft
 thrust bearing;  thrust block
 axon guidance;  axon pathfinding
 vertical shaft;  upright arm shaft
 steering column;  steering shaft
 optic axis (of a crystal);  optical axis
 the eight volumes of the Lotus Sutra
 axial length (of the eye)
 stonewort (esp. Braun's stonewort, Chara braunii)
 bastard lupine (Trifolium lupinaster);  lupine clover;  hop clover;  trefoil