The gill is a unit of measurement for volume equal to a quarter of a pint

Pint

The pint is a unit of volume or capacity that was once used across much of Europe with values varying from state to state from less than half a litre to over one litre. Within continental Europe, the pint was replaced with the metric system during the nineteenth century...

. It is no longer in common use, except in regard to the volume of alcoholic spirits measures but it is also kept alive by the occasional reference, such as in the cumulative song

Cumulative song

A cumulative song is a song whose verses are built from earlier verses, usually by adding a new stanza to the previous verse. A simple cumulative song having n verses is structured as-Examples of cumulative songs:* "The Twelve Days of Christmas"...

, "The Barley Mow

The Barley Mow

The Barley Mow is a cumulative song celebrated in the traditions of the folk music of Ireland, England, and Scotland. William Chappell transcribed the lyrics in his two-volume work The Ballad Literature and Popular Music of the Olden Time ."The Barley Mow" has become a drinking song sung while...

".

Imperial gill

1 imperial Imperial unit The system of imperial units or the imperial system is the system of units first defined in the British Weights and Measures Act of 1824, which was later refined and reduced. The system came into official use across the British Empire...  gill	≡ 5 imperial fluid ounce Fluid ounce A fluid ounce is a unit of volume equal to about 28.4 mL in the imperial system or about 29.6 mL in the US system. The fluid ounce is distinct from the ounce, which measures mass... s
	≡ 142.0653125 ml
	≈ 142 ml
	≈ 1.2 US gills

United States customary gill

1 US United States customary units United States customary units are a system of measurements commonly used in the United States. Many U.S. units are virtually identical to their imperial counterparts, but the U.S. customary system developed from English units used in the British Empire before the system of imperial units was...  gill	≡ 4 US fl oz
	≡ 118.29411825 ml
	≈ 118 ml
	≈ imperial gills

In Great Britain

Great Britain

Great Britain or Britain is an island situated to the northwest of Continental Europe. It is the ninth largest island in the world, and the largest European island, as well as the largest of the British Isles...

, the standard single measure of spirits in a pub was gill (23.7 ml) in England, and gill (28.4 ml) in Scotland

Scotland

Scotland is a country that is part of the United Kingdom. Occupying the northern third of the island of Great Britain, it shares a border with England to the south and is bounded by the North Sea to the east, the Atlantic Ocean to the north and west, and the North Channel and Irish Sea to the...

; though this has now been replaced by either 25 or 35 ml (0.176- or 0.246-gill) measures (Landlords can choose which one to serve). The gill was previously the most common measure in Scotland. In southern England, it is also called a noggin. In northern England, however, the large noggin is used, which is two gills. In some areas, a gill came to mean half a pint for both beer and milk.