A note on this word ærið  I have just heard from Grace of her interest
in our mutual difficulty with the word and Grace did suggest that it
might have a relationship with the word used to mean "Honour" .
I have found an entry in the supplement of CV that had the word -
ærr-lauss - without honour - since neither Grace nor myself have
the notion that it has anything to do with sheep
It seems in the beginning of the chapter that Thjostolf - our friendly
neighbourhood homicidal maniac is protesting his going in search of the
wethers along of Glum's servants whom he calls Thralls then Grace's idea
will be in the right direction - it is beneath this man's over-estimated dignity
to go  searching for sheep.
But ærið is definitely not in the book
I am feeling a trifle sheepish that I had not noticed this before
Patricia