It's a bit of a trick question! Homographs are words that are spelled the same but have different meanings and sometimes different pronunciations. "Jar" has multiple meanings, including:
* A glass container with a wide mouth, used for storing food or drink. (pronounced "jar")
* To shake or vibrate roughly. (pronounced "jar")
So, while the word "jar" is its own homograph, it doesn't have a separate word that's spelled the same but has a different meaning.