I actually had a very similar moment once when a recipe called for a dry sherry, White Dragon. I just assumed it was a special cooking ingredient and browsed around looking for it, then had a "Oh, wait, I bet it means--" moment.
Along these lines, I once had to explain to a guy in the grocery store - and a grocery store employee - what "dry pasta" was.
DH and I were doing our shopping, and I noticed a guy walking through the store with a cookbook open in the cart and an employee walking with him. This is a local chain that's a bit more upscale; they tend to be very about customer service, sell fancier stuff, etc. So I assumed that the employee was helping him find some things he needed.
A few minutes later, DH and I see them again in the dairy section, both looking confused. Being basically nosy
, I asked if I could help. They explained that they were looking for "dry pasta." After retrieving my jaw from the floor, I asked if I could look at the recipe, explained that they needed noodles, and suggested a couple of types I thought would work with the recipe, since there wasn't a specific type listed in the recipe.
They were both appreciative, and we saw them a third time, this time with a bag of noodles in the cart.