In most instances, one adds an S to pluralize a word: all well and good. But when a second S is added, interestnig things begin to happen; suddenly, the word becomes singular again, or takes on an altogether new meaning -- ADVENTURES becomes ADVENTURESS, or CARES becomes CARESS.
Try your hand at identifying the following dual-identity words.
Douglass, Richard E.
"E Pluribus Unum,"
Word Ways: Vol. 14
, Article 5.
Available at: http://digitalcommons.butler.edu/wordways/vol14/iss3/5