Variation
VARIA'TION, noun [Latin variatio. See Vary.]
1. Alteration; a partial change in the form, position, state or qualities of the same thing; as a variation of color in different lights; a variation in the size of a plant from day to day; the unceasing, though slow variation of language; a variation in a soil from year to year. Our opinions are subject to continual variations.
The essences of things are conceived not capable of such variation
2. Difference; change from one to another.
In some other places are born more females than males; which, upon this variation of proportion, I recommend to the curious.
3. In grammar, change of termination of nouns and adjectives, constituting what is called case, number and gender; as the variation of words.
4. Deviation; as a variation of a transcript from the original.
5. In astronomy, the variation of the moon is the third inequality in her motion; by which, when out of the quadratures, her true place differs from her place twice equated.
6. In geography and navigation, the deviation of the magnetic needle from the true north point; called also declination.
The variation of the needle at New Haven, in 1820, as ascertained from the mean of numerous observations made by Professor Fisher, was 4 degrees 25.42' west.
7. In music, the different manner of singing or playing the same air or tune, by subdividing the notes into several others of less value, or by adding graces, yet so that the tune itself may be discovered through all its embellishments.