Cuthbert means 'brilliant light', which leads nicely to the story about St. Cuthbert.
One night in August, 651, the shepherd boy Cuthbert was praying on a hillside near Melrose monastery which lies at the heart of the Scottish Borders. He saw "a great light and a choir of angels" descend from the night sky.
The next day he learned that St. Aidan, Bishop of Lindisfarne, had died the previous night. Cuthbert believed he had witnessed St. Aidan's soul being carried to heaven and took this as a sign of his calling to missionary work. He became Bishop of Lindisfarne on Easter Day, 685.
Many miraculous healings have been attributed to St. Cuthbert and his remains now lie in Durham Cathedral.
Sometimes confused with the Consecration Cross, the St. Cuthbert Cross is seen mainly on heraldic regalia and similar ceremonial wear. To fit the shape of escutcheons (shields) in coats-of-arms, the cross has four equal-length arms. Each arm has a Thor-like hammer head. There is no connection between Thor and St. Cuthbert, except for the influence of Celtic art in the 7th century.
A comparable heraldic cross is the Flanched Cross, so called from the heraldic term for a segment of a circle taken out of the cross arms. It has no particular meaning in Christianity, but may be found in churches where the central quadrants act as structural braces.
The inverse of "flanch" is the similarly-named "flaunch", which is the term used for the convex coving of mortar around a chimney pot, manhole, etc., to divert rainwater. A cross with a convex curve in each quadrant produces a disc, and is called (variously) a Nowy Cross or Sun Cross.