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septillion

septillion

9.9
A very large number that is 1 followed by twenty four zeros
  • noun
  • /sɛpˈtɪljən/
  • US
translation icon : septillón
  • A yottabyte is 1 septillion bytes.

Examples

  • In an average winter, climatologists estimate that approximately 1 septillion snow crystals fall from the sky.

  • We started at a septillion, correct?

  • A yottabyte is 1 septillion bytes.

  • The Sun emits energy equivalent to about 384.6 septillion watts each second.

Synonyms

quadrillion
vsseptillion
  • Archaic
8.0

The number 1 followed by 24 zeros, used in older British number system

is the same number but called that way in the United States

How Big

tredecillion
  • Specialized
9.9
septillion
  • US
9.9
quintillion
1 8.4
quadrillion
1 7.5
trillion
346 2.6
billion
1.0
million
1.0

Surface Forms

septillion singular
septillions plural

Morphology

septillion = million (semi-transparent) = sept + illion

The word is formed by the numerical prefix 'sept-' (seven) attached to the '-illion' naming pattern familiar from 'million' and friends; this signals a very large number but does not make the exact power of ten obvious to learners without knowledge of the -illion sequence.

Etymology

The word septillion comes from the Latin root sept- meaning 'seven' and the familiar word million, because English builds names for very large numbers in steps from million. So, in American English a septillion is the number one followed by twenty-four zeros.