Millimeter
A millimeter (mm) is a very small unit of length in the metric system. It is commonly used to measure tiny objects or precise dimensions. One millimeter is equal to one-thousandth of a meter (1 mm = 0.001 m), and 10 millimeters make 1 centimeter. Millimeters are often used in fields like engineering, machining, and science where exact measurements are important. For example, the thickness of a credit card is about 1 mm. The symbol for millimeter is "mm", and you can find it on most rulers or measuring tools. Since it allows for high accuracy, the millimeter is ideal for measuring small parts, gaps, or details.
Barleycorn
A barleycorn is an old English unit of length, traditionally based on the length of a grain of barley. It is defined as exactly 1/3 of an inch or approximately 8.47 millimeters.
Historically, the barleycorn was used for measuring small lengths and was also the basis for the inch, which was originally considered to be three barleycorns long. It played a role in various traditional measurements, including shoe sizing in English-speaking countries, where shoe sizes were sometimes expressed in barleycorn units.
Although obsolete as a formal unit, the barleycorn remains culturally significant, especially in shoe sizing systems.
Summary:
1 barleycorn = 1/3 inch ≈ 8.47 mm
Based on the length of a grain of barley
Used historically in small measurements and shoe sizing
Mostly of historical and cultural interest today
No conversions available for length.