googol

Etymology

Coined by nine-year-old Milton Sirotta in 1920, nephew of American mathematician Edward Kasner, who had asked Milton to think of a name for the 100th power of ten. The word was first published in the book Mathematics and the Imagination (1940).

num

1. The number 10¹⁰⁰, or ten to the power of a hundred. Equivalent to ten duotrigintillion (short scale), or ten sedecilliard (long scale).
   Words of wisdom are spoken by children at least as often as by scientists. The name "googol" was invented by a child (Dr. Kasner's nine-year-old nephew) who was asked to think up a name for a very big number, namely, 1 with a hundred zeros after it. He was very certain that this number was not infinite, and therefore equally certain that it had to have a name. […] A googolplex is much bigger than a googol, much bigger than a googol times a googol. A googol times a googol would be 1 with 200 zeros, whereas a googolplex is one with a googol of zeros. You will get some idea of the size of this very large but finite number from the fact that there would not be enough room to write it, if you went to the farthest star, touring all the nebulae and putting down zeros every inch of the way. 1940, Edward Kasner, James [Roy] Newman, “New Names for Old”, in Mathematics and the Imagination, New York, N.Y.: Simon & Schuster, →OCLC, page 23
   For example, in considering all the finite state grammars that use seven terminal symbols and seven auxiliary symbols (states), … he must test over a googol (10^100) candidates. 1979, Steven Pinker, “Formal models of language learning”, in Language, Cognition, and Human Nature
   If the universe were packed solid with neutrons, say, so there was no empty space anywhere, there would still only be about 10¹²⁸ particles in it, quite a bit more than a googol but trivially small compared to a googolplex. 1980, Carl Sagan, chapter IX, in Cosmos