The gallon is a unit of volume in the imperial unit system with the symbol gal.
1 British imperial gallon is defined as 4.54609 litres or 277.4194 in³.
The term gallon derives directly from the Old Northern French term 'galun' which means 'liquid measure'. The origin of the word prior to this is still unknown. It originated as the base of the system for measuring wine and beer in the UK and has now been adopted across the world and there are similar versions in the US and associated states (although they measure slightly differently).
The bushel is a unit of volume in the imperial unit system with the symbol bsh.
1 bushel is equal to 8 dry gallons, or 36.36872 litres.
The bushel was introduced in England as a unit to bridge the relatively large gap between a pound and a ton - and was used largely to measure volumes of liquid being imported and exported following the Norman Conquest such as wine and ale.
The name bushel comes from the ancient French 'boissiel' which means 'little box'.