Not that they're the arbiters of sense, but this was taken from MS Word. This is shown when it shows a list of known words starting with the same letter as the query word.
The only way I can see that you could change it at present is to implement a custom UI (as per our example project) and then capture DataSource changed events on MeaningsListBox, which would allow you to find the text and change it.
I'll add it to feature request list for next version (unsure when that'll be released at moment).
Best,
Jim
-your feedback is helpful to other users, thank you!