It won't accept words that are just plurals of shorter words, like—well words. Fairly sure this is in accord with the word list for this whole Wordlelike genre. Even games that might accept plurals as valid guesses will never actually have them as the correct answer.
We'll push a new update in the next few days with some improvements in the valid/answers word lists! (Right now we're working in the localization module, but after that, lists get priority!)
