a hin: a unit of liquid measure (about three and a half liters, a sixth of a bath), used for oil, wine, and water
The hin is a container-sized measure of liquid, holding roughly three and a half liters, a little under a gallon. It sits in the middle of Israel's system of liquid measures: six hin make one bath (the largest liquid measure), and one hin divides into twelve of the smallest unit, the log. The word itself was almost certainly borrowed from Egyptian, where a similar term named a standard jar.
Almost every time the hin appears, it is measuring out an ingredient for worship. The instructions for the daily and festival offerings call for set fractions of a hin of oil to be mixed into grain offerings and matching amounts of wine poured out as drink offerings: a quarter of a hin, a third, or a half, scaled to the size of the animal being offered. A full hin of finely pressed olive oil goes into the sacred anointing oil in Exodus 30:24. In Ezekiel's vision of a restored temple, the prophet drinks his rationed water by the sixth of a hin, and the same measure sets the oil for the offerings there.
One appearance stands apart from the altar. In the command to use honest weights and measures, a "just hin" is named alongside honest scales and an honest dry measure, making the hin a benchmark of fair dealing as well as a tool of the sanctuary.
Because it is a fixed unit rather than a describable object, English Bibles simply carry the word over as "hin" rather than translating it.