Meaning of VARIABLE in English
/ ˈveəriəbl; NAmE ˈver-; ˈvær-/ adjective , noun
often changing; likely to change
SYN fluctuating :
The acting is of variable quality (= some of it is good and some of it is bad) .
able to be changed :
The drill has variable speed control.
► vari·ably / -iəbli; NAmE / adverb
a situation, number or quantity that can vary or be varied :
With so many variables, it is difficult to calculate the cost.
The temperature remained constant while pressure was a variable in the experiment.
late Middle English : via Old French from Latin variabilis , from variare , from varius diverse.
Oxford Advanced Learner's English Dictionary. Оксфордский английский словарь для изучающик язык на продвинутом уровне. 2005