Breathing is then done through the tube, bypassing the mouth, nose, and throat. A tracheostomy is commonly referred to as a stoma. This is the name for the hole in the neck that the tube passes through.
A millimeter (mm) is the smallest. In order from smallest to largest they rank millimeter, centimeter (cm), decimeter (dm), and meter (m). These are all common units of length in the metric system.
The base unit of length for the metric system and the International System of Units (SI). Defined as the exact distance light travels in an absolute vacuum in 1/299 792 458 of a second. Originally, in 1791, the meter was defined as 1/10 000 000 of the distance between the equater and the North Pole through Paris. Then in 1889 and lasting until 1960 the meter was defined as the exact length of a metal bar kept under certain conditions. In 1960 the definition changed again to be 1 650 763.73 wavelengths of the orange-red emission line in the electromagnetic spectrum of the krypton-86 atom in a vacuum.