Definitions in math formulas

Question

I want to have definitions like $x :=1$ in my tex to look good, and to be really different from a statement of equality like $x = 1$.

However, the $:$ and $=$ are not alligned, and this looks ugly.

How do I overcome this?

Answer 1

See this. The package mathtools provides 'coloneqq' (:=) and 'eqqcolon' (=:).