Switching the plot variable when plotting a two-variable function as a single variable function with a parameter

I would like to make easy to change the variable for which I am making a set of plots. Say I want to plot Sin, Tan, Cos and other functions of the same argument. To quickly switch from plotting it as function of x or y I wanted to use a "dummy" plot variable var and assing it to y or x depending on the need.

x = 1; var = y;
Plot[Sin[x*y], {var, 1, 2}]
Plot[Tan[x*y], {var, 1, 2}]
Plot[Cos[x*y], {var, 1, 2}]
Unset[{x, y, var}];


Unfortunately this doesn't quite works because var in the range specification {var,1,2} is not evaluated.

Any suggestions?

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Evaluate@{var, 1, 2}... – ciao May 5 '14 at 7:53
great! it works, but what is the difference with respect to Evaluate[var] which was my trial before posting here? – Roberto Franceschini May 5 '14 at 10:16
I can't check it but as far as I remember Evaluate works only on first level. – Kuba May 5 '14 at 13:37

x = 8; var = y;