Q:

What's the difference between aqueous NaOH and dilute NaOH?

Dilute $\ce{NaOH}$ can be prepared by adding a suitable amount of concentrated $\ce{NaOH}$.

What's the difference between "dilute $\ce{NaOH}$" and "aqueous $\ce{NaOH}$"?

A:

Dilute simply means that the concentration of the solute of interest, in this case $\ce{NaOH}$, is low relative to some reference.  One could imagine a non-aqueous, dilute solution of $\ce{NaOH}$ in, say, methanol.
An aqueous solution is one where the solvent is water, regardless of the concentration of the dissolved solute(s).
So, for example, the following combinations of the terms are possible:

Concentrated aqueous solution - High $\ce{NaOH}$ concentration in a water solvent
Dilute aqueous solution - Low $\ce{NaOH}$ concentration in a water solvent
Concentrated methanolic solution - High $\ce{NaOH}$ concentration in a methanol solvent
Dilute methanolic solution - Low $\ce{NaOH}$ concentration in a methanol solvent

