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1. The cardinal number equal to 1036.
2. Chiefly British The cardinal number equal to 1066.

[Latin undecim, ūndecim (ūnus, one; see oi-no- in Indo-European roots + decem, ten; see dekm̥ in Indo-European roots) + (m)illion.]

un′de·cil′lion adj.
un′de·cil′lionth adj.adv. & n.
American Heritage® Dictionary of the English Language, Fifth Edition. Copyright © 2016 by Houghton Mifflin Harcourt Publishing Company. Published by Houghton Mifflin Harcourt Publishing Company. All rights reserved.


(Mathematics) ten to the power of thirty-six
Collins English Dictionary – Complete and Unabridged, 12th Edition 2014 © HarperCollins Publishers 1991, 1994, 1998, 2000, 2003, 2006, 2007, 2009, 2011, 2014


(ˌʌn dɪˈsɪl yən)

n., pl. -lions, (as after a numeral) -lion, n.
1. a cardinal number represented in the U.S. by 1 followed by 36 zeros, and in Great Britain by 1 followed by 66 zeros.
2. amounting to one undecillion in number.
[1930–35; < Latin undec(im) eleven (ūn(us) one + -decim, comb. form of decem ten) + -illion, as in million]
un`de•cil′lionth, adj., n.
Random House Kernerman Webster's College Dictionary, © 2010 K Dictionaries Ltd. Copyright 2005, 1997, 1991 by Random House, Inc. All rights reserved.
References in periodicals archive ?
TWIN Caching systematically caches and analyzes over 340 undecillion IP addresses, going beyond traditional IP association to uncover last-mile connectivity ownership.
A key twice the length, or 128 bits, would have 2A[sup.1]A[sup.2]a[cedilla] possible solutions 6 more than 300 undecillion, or a 3 followed by 38 zeroes.
However, the odds of getting 12 double yolkers consecutively are a massive undecillion to one.
One egg: 1,000 (thousand) Two eggs: 1,000,000 (million) Three eggs: 1,000,000,000 (billion) Four eggs: 1,000,000,000,000 (trillion) Five eggs: 1,000,000,000,000,000 (quadrillion) Six eggs: 1,000,000,000,000,000,000 (quintillion) Seven eggs: 1,000,000,000,000,000,000,000 (sextillion) Eight eggs: 1,000,000,000,000,000,000,000,000 (septillion) Nine eggs: 1,000,000,000,000,000,000,000,000,000 (octillion) 10 eggs: 1,000,000,000,000,000,000,000,000,000,000 (nonillion) 11 eggs: 1,000,000,000,000,000,000,000,000,000,000,000 (decillion) 12 eggs: 1,000,000,000,000,000,000,000,000,000,000,000,000 (undecillion) Niki Tennant A shell-shocked mum hit the breakfast jackpot when she and her husband cracked open two boxes of eggs from a Wishaw dairy -and all 12 were double yolkers.
340 undecillion, 282 decillion, 366 nonillion, 920 octillion, 938 septillion, 463 sextillion, 463 quintillion, 374 quadrillion, 607 trillion, 431 billion, 768 million, 211 thousand and 456.
Enraged Anton Purisima, 62, filed a lawsuit calling for two undecillion dollars - $2,000,000,000,000, 000,0 00,000,000,000,000,000,000.
This is 34 with 37 zeros after it, or 340 undecillion, with the
Short scale Long scale billion [10.sup.9] milliard trillion [10.sup.12] billion quadrillion [10.sup.15] billiard quintillion [10.sup.18] trillion sextillion [10.sup.21] trilliard septillion [10.sup.24] quadrillion octillion [10.sup.27] quadrilliard nonillion [10.sup.30] quintillion decillion [10.sup.33] quintilliard undecillion [10.sup.36] sextillion duodecillion [10.sup.39] sextilliard tredecillion [10.sup.42] septillion
A vastly increased I 28-bit capacity provides a total of 340 undecillion unique addresses (3.4 x [10.sup.38]), which to put into perspective is 480,000,000,000,000,000,000,000,000,000 IPv6 addresses for every single one of the 7 billion people on the planet, compared to the 4,294,967,296 possible IPv4 addresses currently available (0.6 IPv4 addresses for every person).
Three hundred and forty undecillion, two hundred and eighty-two decillion, three hundred and sixty-six nonillion, nine hundred and twenty octillion, nine hundred and thirty-eight septillion, four hundred and sixty-three sextillion, four hundred and sixty-three quintillion, three hundred and seventy-four quadrillion, six hundred and seven trillion, four hundred and thirty-one billion, seven hundred and sixty-eight million, two hundred and eleven thousand, four hundred and fifty-six.
According to The Daily Mail, IPv4 provided 4.3billion addressees, while the new system brings with it 340 undecillion potential IP addresses.