5-letter words only. Replace one letter to make a new one. rearranging letters are fine but only one letter may be replaced with another to form a 5-letter word. (Edited for clarity). Farce
shine Only one letter was replaced: "m" was replaced by "s". Rearranging the order doesn't matter. But only one letter may be replaced. The key word is "replace" one letter. Not "rearrange" one letter.