As I've probably said before, Darrigol's excellent Worlds of Flow confuses me by, quite correctly to Rayleigh (who had assumed his title before doing most of his work) and Thomson (who didn't get his till after)

Recent concerns about who gets things named after them rather obscure the fact that the whole business of named theorems and definitions in maths is a horrible kludge that wouldn’t be fixable even if we renamed everything from scratch