Y

Summary

yard (noun): a native English word that no longer resembles its presumed ancestor, the Indo-European root ghasto- “a rod, a staff.” In Old English the fore-runner of yard meant “a straight shoot, a twig, a rod, a staff.” Only after about the year 1000 did the term come to designate a specific length of 3 feet, although a yard was also sometimes defined as 16.5 feet, a length that later came to be called a rod. The word yard referring to a length is only coincidentally spelled and pronounced the same as the historically different word yard referring to an enclosure, as in the front yard of a house.

year (noun): a native English word, from the Indo-European root yer-, of the same meaning. The Indo-European word also developed the meaning “season,” as seen in Old Slavonic (the predecessor of modern Russian) yara “spring” and in Greek hora “season.” The designated amount of time grew even shorter when the Romans borrowed the Greek word and used it to mean hour. [258]

yocto-, abbreviated y (numerical prefix): in the International System of Units the prefix yocto- multiplies the unit to which it is attached by 10^-24, which can be rewritten as (10^-3)⁸, the eighth power of one one-thousandth. Yocto- is from Greek okto or Latin octo “eight,” the final -o of which already complies with the current system: all of the numerical prefixes in the International System have two syllables and end in a vowel, which in the case of submultiples created in recent times is always an -o.