When your girlfriend says “your dick is the perfect size for me” it means she prefers your dick size to other sizes. If she say “I love your dick it’s the perfect size” I’m sorry but she’s sparing you and finally the tricky one. If she says “I don’t like big dick it hurts me, your dick is the perfect size” it means she could be telling the truth but it’s just hard to say.
Short-hand for the word floccinaucinihilipilification, meaning the estimation of something as valueless (encountered mainly as an example of one of the longest words in the English language).