How do dictionaries monetize

Hi all,

I recently started building an app that's sort of scratching my own itch - learning English. It's a small and fast dictionary implemented as a Chrome extension. Compared to competitors, I believe it will have a much better UX and, if I see some traction, I can dedicate time to making other features such as pronunciation better.

I am assuming there is quite some market, because there's extensions with 100k users according to chrome stats.

However, I have never seen, or rather used or was going to use, a dictionary with a subscription so perhaps the juiciest monetization model isn't gonna work.

Do you know how other dictionaries and similar products make money?