There was a period of time when the kids were younger when Hubby and I got in the habit of calling each other "diphthong" as a teasing insult. I don't even vaguely remember how it got started, but I know that at one point, Hubby called Youngest Sister that and she quickly came back with "Umlaut!" To which he responded, "Schwa!"
You not only had to be there for that one, you also had to be a little bit of a geek.
Flash forward to this afternoon. Phone call from Son-One, "Mom, what's a diphthong? I just called Girlfriend-One a diphthong and she didn't know what it means and I just realized I don't really know how to explain it."
Ah, Son-One perhaps you should worry a little less about the defintion of diphthong and a little more about what other quirky time-bombs are left behind from your childhood...
The DH (Designated Human)
7 hours ago