URL variables NOT used as form field selection?

URL variables NOT used as form field selection?

I basically want to be able to pass a variable via URL to a form - but use that one word in a description field.  Is this possible?

Example:

User clicks on button - url variable is ?product=Bestproduct
Put that variable in the sentence so a description field at top reads:

Thanks for asking about {Bestproduct}!

Is this possible?