The Wiki entry on Coulsdon claims to give a huge variety of spellings of the name -- literally a couple of dozen -- having appeared over the centuries; with final informational gem, about name possibly being derived from the Celtic or primitive Welsh cull, "meaning leather bag, scrotum, bosom, womb or belly". I'm convinced that now and again, somebody bent on "having a laugh" sneaks crazy stuff of their own invention, past Wiki's guardians... In apparently more sober fact: a settlement with considerably varied times-past spellings -- though certainly not in the dozens -- is Crowland (alias Croyland), Lincolnshire.