In my linguistics class we were talking about “insertion” which is basically when you say a word and pronounce an extra letter or sound even though it’s not written in the word itself, to which my professor used the example of “hamster” because when you say it you pronounce a “p” even though it’s not written and this group of guys were going through an existential crisis because they couldn’t believe they said hamster with a “p” and one kid began to question everything in his life and it was beautiful
My favourite example along these lines is the hidden nasal sounds in English that you don’t even realize you’re producing. Everyone knows about /m/ and /n/ because they have distinct letters, but there’s also a sound that’s often written “ng” and yet not actually pronounced as n+g. For example, “ng” in “finger” is pronounced like “n+g” but “ng” in “singer” is a totally distinct sound (known as “engma” and written /ŋ/ in the IPA).
Even more obscurely, /m/ is normally produced with a closure of the two lips, but when it’s found before /f/ or /v/, it gets pronounced with the teeth on the lips instead, just like /f/ and /v/ are, as in “comfort” or “symphony”. The IPA symbol for this is /ɱ/, and I don’t think it technically has a fun name, but I call it “emfma” by analogy with “engma” and every linguist I’ve said it to has understood me.