Micron
A micron is another name for a micrometer, a very small unit of length in the metric system. One micron equals one-millionth of a meter (1 micron = 1 µm = 0.000001 meters). Microns are used to measure extremely small things like bacteria, cells, dust particles, or the thickness of hair and fibers. For example, a human hair is about 70 microns thick. The symbol for micron is "µm". Though “micron” is an older term, it is still commonly used in fields like biology, electronics, and materials science to describe microscopic measurements.
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.