Afreca nic Fergus of Gallloway, Princess of Isle of Man - I find it hard to understand that Olav I Morsel / The Red and what nickname otherwise he was known of; that he as king has to be a dwarf

Óláfr bitlingur

it could be for any number of reasons, i don't know why this is.

runt
puny
lump
chunk
snack
scion
snippet
handful
remnant

or ironic use maybe, to mean the opposite

kleining = midget

I guess that they just have invented the meaning of Bitling=dwarf, in swedish it called bettleri, it means begging, Olof the begger. You van ask for money, support, or a womans hand, (offer of marriage proposal), maybe he just spent a lot of his time on his knees?

biti is a bite, bitlingur is the diminuitive of a bite so "a wee bite" or a morsel

or in street parlance, an example "spare me a dime, mister?" is panhandling, i.e. begging

in the example, dime (small coin) = small piece = bitlingur (by analogy)

"give us a crumb" :)