1》 not consistent or having a fixed pattern; liable to vary.
↘ Mathematics (of a quantity) able to assume different numerical values.
↘ Botany & Zoology (of a species) liable to deviate from the typical colour or form, or to occur in different colours or forms.
2》 able to be changed or adapted.
↘(of a gear) designed to give varying ratios or speeds.
■ noun a ~ factor or quantity.
↘ Astronomy a star whose brightness changes (regularly or irregularly).
↘( ~s ) the region of light, ~ winds to the north of the NE trade winds or (in the southern hemisphere) between the SE trade winds and the westerlies.