Diseased or unhealthy from consuming too much grain; or relating to illness caused by grain poisoning or mold toxins in stored grain.
From grain plus sick (from Old English seoc). The compound describes conditions arising from grain consumption, particularly relevant to animals or people in agrarian societies.
Before modern food safety, ergot fungus on moldy grain poisoned entire villages with a condition called 'grain sickness'—creating hallucinations and convulsions that some historians think fueled witch trial hysteria.
Complete word intelligence in one call. Free tier — 50 lookups/day.