Variation

noun
1.
the act, process, or accident of varying in condition, character, or degree:
Prices are subject to variation.
2.
an instance of this:
There is a variation in the quality of fabrics in this shipment.
3.
amount, rate, extent, or degree of change:
a temperature variation of 40° in a particular climate.
4.
a different form of something; variant.
5.
Music.

the transformation of a melody or theme with changes or elaborations in harmony, rhythm, and melody.
a varied form of a melody or theme, especially one of a series of such forms developing the capacities of the subject.

6.
Ballet. a solo dance, especially one forming a section of a pas de deux.
7.
Astronomy. any deviation from the mean orbit of a heavenly body, especially of a planetary or satellite orbit.
8.
Also called magnetic declination, magnetic variation. Navigation. the angle between the geographic and the magnetic meridian at a given point, expressed in plus degrees east or minus degrees west of true north.
Compare deviation (def 4).
9.
Biology. a difference or deviation in structure or character from others of the same species or group.
noun
1.
the act, process, condition, or result of changing or varying; diversity
2.
an instance of varying or the amount, rate, or degree of such change
3.
something that differs from a standard or convention
4.
(music)

a repetition of a musical theme in which the rhythm, harmony, or melody is altered or embellished
(as modifier): variation form

5.
(biology)

a marked deviation from the typical form or function
a characteristic or an organism showing this deviation

6.
(astronomy) any change in or deviation from the mean motion or orbit of a planet, satellite, etc, esp a perturbation of the moon
7.
another word for magnetic declination
8.
(ballet) a solo dance
9.
(linguistics) any form of morphophonemic change, such as one involved in inflection, conjugation, or vowel mutation

variation var·i·a·tion (vâr’ē-ā’shən, vār’-)
n.

The act, process, or result of varying.

The state or fact of being varied.

The extent or degree to which something varies.

Something slightly different from another of the same type.

Marked difference or deviation from the normal or recognized form, function, or structure.

An organism exhibiting such difference or deviation.

A function that relates the values of one variable to those of other variables.