deciüillion

A deciüillion is a hypothetical unit used in speculative discussions of extremely large numbers. It is derived from the prefix "deci-" which represents one tenth, and the suffix "-üillion" which is a portmanteau of "illion" and a hypothetical symbol or sound "ü" intended to suggest a very large, undefined quantity. The exact value of a deciüillion is not standardized and depends entirely on the context in which it is used, as the "-üillion" suffix itself lacks a formal mathematical definition.

In theoretical discussions, a deciüillion might be conceptualized as a fraction of an even larger, similarly undefined number. For instance, if "üillion" were to represent a number with a certain number of zeroes, a deciüillion would represent one tenth of that. However, since "üillion" is not a recognized term in mathematics or science, there is no agreed-upon scale or base value to which "deci-" can be applied. Its usage is primarily for illustrative purposes in thought experiments or creative writing exploring the limits of scale.

The term "deciüillion" does not appear in standard scientific, mathematical, or engineering literature. Its existence is confined to niche discussions where individuals might invent or coin terms to express exceptionally vast, often immeasurable, quantities that exceed commonly used large number names like vigintillion or googol. The flexibility of its definition means it can be adapted to represent any fraction of an arbitrary "üillion."