Groats, also known as grits, are oats or corn from which the husk has been removed. The oats or corn are hulled and ground to a coarse meal which is used for making porridge, gruel and broths.
Nowadays, the term grog is generally applied to any warming drink containing a spirit, usually rum, and lemon, sugar and hot water. The term originated in the mid-eighteenth century when Admiral ‘Grogram’ Vernon ordered the Royal Navy’s traditional – and strong – rum ration to be watered down.
Various expressions have arisen from the word – ‘seven-water grog’ means an extremely weak rum, for instance, and to feel ‘groggy’ means to be drunk.