var·i·a·tion 
/ˌveriˈeɪʃən/ noun
plural var·i·a·tions /ˌveriˈeɪʃən/ noun 1 : a change in the form, position, condition, or amount of something [count] ▪ color/temperature variations — often + in ▪ extreme variations in temperature [noncount] ▪ He repeated the story without variation. [=without changing it] — often + in ▪ There's been a lot of variation in the weather lately. [=the weather has changed often lately] ▪ We need some variation in our routine. [=we need to change/vary our routine] 2 [count] : something that is similar to something else but different in some way — often + on ▪ His newest book is just a slight variation on a familiar theme. ▪ The meal she served us was an interesting variation on a traditional turkey dinner. 3 [count] music : a repeated version of a short piece of music with changes in its rhythm, tune, or harmony — often + on ▪ variations on a theme by Haydn
