Definition of morphological axis in US English:

morphological axis

noun

  • 1Crystallography (now rare, perhaps Obsolete), the axis of rotational symmetry of a crystal system; the line of intersection of two planes of symmetry of a crystal system.

  • 2(More generally) a line representing an axis of symmetry, or the longest linear dimension, in the shape of an object.

Origin

Late 19th century; earliest use found in Henry Palin Gurney (1847–1904), educationist.