tredecillion

From Latin tredecim (“thirteen”) +‎ -illion.

• Rhymes: -ɪljən

tredecillion (plural tredecillions)

1. (rare, US, modern British & Australian, short scale) 10⁴².
   • 1896, Frank H. Hall, The Werner Arithmetic, Oral and Written, Book Two, Parts I and II:

     The names of the periods above trillion are as follows [...] 15th, tredecillion [...]

   • 1946, United States Department of Commerce, The United States Department of Commerce: How it serves you on land and sea and in the air:

     3 quindecillion, 657 quattuordecillion, 262 tredecillion; which is to say the figures 3,657,262 followed by 42 ciphers. Operators of the key punch machines transfer a code symbol from the Census [...].

   • 1994, National Council of Teachers of Mathematics, The Arithmetic Teacher, National Council of Teachers of Mathematics (1994):

     The answer is read as: 13 sexdecillion, 253 quindecillion, 796 quattuordecillion, 742 tredecillion, [...].

2. (rare, dated, British, Australia, long scale) 10⁷⁸.

• (10⁴²): a long scale septillion
• (10⁷⁸): a short scale quinvigintillion

• (short and long scale) Previous: duodecillion. Next: quattuordecillion.

• Words of Mathematics: An Etymological Dictionary of Mathematical Terms Used in English (1994).