My understanding of shibboleth is that it refers to the primary pronunciation identifying the speaker (which is how it was used biblically). Those are also int

My understanding of shibboleth is that it refers to the primary pronunciation identifying the speaker (which is how it was used biblically). Those are also interesting but it feels a bit more special to me when it's a secondary speech characteristic because it feels a bit more like a clue in a detective novel -- it almost feels like you can hear inside the author's head and how they vocalise while they write. In this case, "missle" is a malapropism that is only possible if you don't pronounce the second "i", and so is a secondary "speech" characteristic.