Hello Mary,
This is certainly a hard one! Do you have any more details of William? Age? Occupation, name of wife if married, etc etc.
I wondered whether the name could be More? That was a forename used for both males and females according to the IGI. Perhaps its origin is from variant spellings of a surname - Muir, More, Moor, Moore (I have a place name in Fife which is variously spelled as Muircockhall or Moorcockhall).
Can't find a More BURGES/S on FreeCEN but there are a couple of males (father and son) with 'More' as their forename (they are in Midlothian, surname is given as Cocburn and they appear in the IGI). Unfortunately, however, there are no deaths on ScotlandsPeople for a More/Moor/Moore BURGES*. There are a couple for a Muir BURGESS but they are in the mid-1900s.
Trying to think laterally, I am also wondering whether what looks like an 'e' at the end of the forename might actually be a curly start to the 'B' of the surname. Not that this would help! It's a pity one can't clearly see the top of the join between what looks like an 'o' and what looks like an 'r'. Could the up stroke of the supposed 'o' not really be joined to make an 'o' but be the start of the 'r' (as in the rather unusual 'r' in the surname). Again not any help. Assuming both of these ideas, one might (using plenty of imagination) make it into Axer - but I've never seen that as an abbreviation of Alexander!
Final suggestion - submit a Contact Form to SP and say you are having great difficulty reading the forename of the witness. I would expect them to pass the query on to GROS - someone there might have an idea or, at least, you might be sent a clearer paper copy.
Good luck,
JAP