rotor shaft

English Thesaurus

1. the axis around which the major rotor of a helicopter turns (noun.artifact)

hypernym	:	axis, axis of rotation,
definition	:	the center around which something rotates (noun.artifact)

part meronym	:	main rotor,
definition	:	rotor consisting of large rotating airfoils on a single-rotor helicopter that produce the lift to support the helicopter in the air (noun.artifact)