Early corruption of French aveugler (“to blind, to delude”),
from aveugle (“blind”),
from the Old French avugle (“without eyes”),
from Latin ab + oculus (“eye”).
The in- might be from other a-/en- variations found in Middle English, which was then latinised into in-.
The sound change from Latin aboculus to Old French avugle is difficult for me to deduce, so I wonder whether it is regular and is there any other example like this?