zetta-

1. a combining form that denotes a factor of the seventh power of 1,000 (10 21 ), used in the names of units of measure.

Word History and Origins

Origin of zetta-¹

First recorded in 1990–95; possibly an alteration of Greek zêta, which is the sixth letter of the final version of the Greek alphabet (representing Latin z ). Greek zeta had the numerical value of seven: it replaced the original sixth letter of the Greek alphabet, wau, which was shaped like the Latin F and was pronounced like w, but the sound and the letter wau became obsolete in most Greek dialects during the 8th century b.c.

Example Sentences

Zetta gave $2.50 a week for a furnished hall bedroom and the use of a bath-room.

From Project Gutenberg

Words That Use zetta-

What does zetta- mean?

Zetta- is a combining form used like a prefix meaning “one sextillion (1021).” It is very occasionally used in scientific terms to name units of measure.

Zetta- may come from Greek zêta, the sixth letter of the Greek alphabet. However, it may also be an alteration of the Latin septem, meaning “seven,” a reference to zetta- being equivalent to 10007.

Zetta- may come from Greek zêta, the sixth letter of the Greek alphabet. To learn more, check out our entry to zeta. However, it may also be an alteration of the form septi-, meaning “seven,” which is a reference to how zetta- is equivalent to 10007; compare with zepto-, meaning “one sextillionth,” by reading our Words That Use article on that form.

Examples of zetta-

One example of a unit that uses the form zetta- is zettahertz, “one sextillion (1021) hertz.”

The form zetta- means “one sextillion,” as we know. A hertz is a “unit of a frequency equal to one cycle per second.”

What are some words that use the combining form zetta-?

• zettabyte
• zettagram
• zettasecond
• zettaton

What are some other forms that zetta- may be commonly confused with?

• septo-
• zetta-
• -zilla
• zygo-

Break it down!

Given the meaning of the form zetta-, what is a zettasecond?