How many relatively common singular nouns can you think of that, when you remove an "s", become a relatively common plural noun?
For example: PRINCESS (singular) becomes PRINCES (plural).
I know of at least four more, one of which only has one "s" to begin with.
(In reply to
re: I believe there are more than these.... (spoiler) by brianjn)
I intentionally did not specify that the initial singular noun should end with an "s" because I was hoping people would come up with some that were NOT in that form. SLICE - LICE was the only one I found unless you count STRAITS (sometimes used singularly - iffy at best) - TRAITS.
I would like to say that Dej Mar's list has a lot of what I would consider to be rather UNcommon words, particularly among the plurals. The only one that I had that was not included in Dej Mar's list was DEADLINESS - DEADLINES.