Hi Simon! As someone who studied Irish for many years, I recognised the CAM element right away. It is very common in personal names - ie. Cameron < Cam-shrón "Crooked Nose", or Campbell < Cam-béal "Crooked Mouth", etc. The BAN element was rather obscure, and I thought that the most likely candidates were CAM-BEANN "(crooked) horn, antler, prong" or CAM-MHUIN "wry-neck". The other possibility, the name Cammán, may be right, but I must say I've never come across this name before. Regarding BH, as with MH, in Ulster dialect it is pronounced as "w", but in the rest of Ireland as "v". Thus, CAM-MHUIN, if pronounced as a "v", might have been heard as "b" (especially since in Old Irish, it was a bilabial "v"). I admit it is a tricky problem, though, with no easy answer. Also, other interesting examples of P/B > C in Irish are Cáisc < Lat. Pascha- "Easter", Corcra < Lat. Purpura "purple" or Cruithne, which is cognate with Briton. However, later borrowings didn't do this, thus Páiste "child" < Anglo-Norman 'Page'. This gives a rough guide to when certain words were borrowed Germanic languages similarly have "p" as a relatively rare sound. Some are inherited from PIE "b", which was also a very rare sound (ie. djúpr "deep" < PIE "b"), but the vast majority of "p" words are borrowed (ie. prestr "priest"). Vertu heill! Dan