From Wiktionary, the free dictionary
From Old French bon, from Latin bonus.
bouan m
- (Guernsey) good
1903, Edgar MacCulloch, “Proverbs, Weather Sayings, etc.”, in Guernsey Folk Lore[1], page 513:Chàngement d'herbage est bouan pour les jânes viaux.- Change of pasture is good for young calves.