Although yod is the smallest Hebrew letter (similar to the Greek iota ı),** its ancient form was much larger, looking more like yad “hand” (from shoulder to middle finger). It is the most frequent letter in modern Hebrew spelling (about 11 percent of words), representing the consonant y and vowels i and e.
It is often missing in short i vowels in biblical Hebrew, as dbr (which in modern Hebrew is usually dybr) is dibber “spoke.” The consonant y in modern Hebrew is often written with two yods, as myyn = miyen (verb), meaning “sorted,” as opposed to myn = min (noun), “sort, kind.”
*Yod also has the numerical value 10, thus “kittah” yod (10th grade).
**Hence, the English words jot or iota, for “write quickly” or “tiny amount.” A Hebrew expression “qotso shel” yod means “trifle detail.”
Yona Sabar is a professor of Hebrew and Aramaic in the department of Near Eastern Languages & Cultures at UCLA.