Whew! I finally got that last riddle, though I'm not sure if I like my husband's hint. I thought and thought and couldn't get it, and I broke down and asked for a hint after a few days and asked how he got it. (we'd already established the first letter and the last 3 letters of the "singular" word). He said, well I was thinking of you, and the word came to me. Hmmmm, is that in a good way?
Then this morning I couldn't sleep, and I thought of this variation of an oldie:
You have an unmarked 5 cup container and an unmarked 9 cup container and unlimited water and a sink. Using only these containers and being able to fill up and pour out in the sink, how could you measure out exactly: 1C, 2C, 3C, ...., 12C, 13C, and 14C?