Some words just make us laugh because they sound silly or strange. It's kind of like when you see someone make a silly face and it makes you giggle. The same thing happens with some words.
For example, the word "bubble" might sound funny because it's just a fun word to say out loud. Or the word "fart" might make you laugh because it sounds like a noise that's funny or embarrassing.
Another reason why some words are funny is because they sound unusual or unexpected. For instance, the word "flibbertigibbet" is a funny-sounding word because it's not a word that you hear very often.
Overall, there isn't really a specific reason why some words are funny and others aren't. It just depends on how it sounds and how it makes us feel. So next time you hear a word that makes you laugh, just enjoy it and let yourself have a good chuckle!