duodecillion
C1/C2Formal / Technical
Definition
Meaning
A cardinal number representing the quantity of one followed by 39 zeros (short scale) or one followed by 72 zeros (long scale).
A very large, abstract number used primarily in theoretical mathematics, astronomy, cosmology, or for hyperbolic emphasis.
Linguistics
Semantic Notes
The numerical value is context-dependent (short scale vs. long scale). In modern English, the short-scale definition (10^39) is standard in the US and increasingly in the UK. It is almost exclusively used in scientific or speculative contexts, not in everyday quantification.
Dialectal Variation
British vs American Usage
Differences
The primary difference is historical, relating to the long-scale (UK traditional) vs. short-scale (US & modern UK) naming systems. A UK traditionalist might interpret 'duodecillion' as 10^72, while in modern American and scientific English, it is 10^39.
Connotations
No specific emotional connotation difference. In both regions, it signifies an unimaginably vast quantity.
Frequency
Extremely low frequency in both varieties. Its use is confined to highly technical or popular science texts discussing vast quantities.
Vocabulary
Collocations
Grammar
Valency Patterns
[Verb] a duodecillion [noun][Number] duodecillion[Preposition] duodecillionVocabulary
Synonyms
Strong
Neutral
Weak
Vocabulary
Antonyms
Phrases
Idioms & Phrases
- “Not a duodecillion miles away (humorous hyperbole for 'quite near')”
Usage
Context Usage
Business
Virtually never used. Potential hyperbolic use: 'The potential market is worth duodecillions.'
Academic
Used in theoretical mathematics, combinatorics, cosmology (e.g., estimating quantum states in a volume of space).
Everyday
Almost never used. May appear in quizzes, trivia, or as an example of a large number name.
Technical
Primary domain. Used in papers on number theory, astronomical calculations of stellar particles, or cryptographic key spaces.
Examples
By Part of Speech
verb
British English
- The theoretical model could duodecillion-fold the possible outcomes. (extremely rare/constructed)
American English
- (No standard verb form exists)
adverb
British English
- (No standard adverb form exists)
American English
- (No standard adverb form exists)
adjective
British English
- They calculated a duodecillion-part function.
American English
- The duodecillion-dollar question is purely theoretical.
Examples
By CEFR Level
- The number duodecillion is very, very big.
- A duodecillion is more than a trillion and much bigger than a billion.
- Some scientists estimate the number of atoms in the observable universe to be less than a duodecillion.
- In the short-scale system, a duodecillion is 10^39, a figure occasionally referenced in cosmological models concerning quantum fluctuations.
Learning
Memory Aids
Mnemonic
Think 'DUO' (two) + 'DEC' (ten) + 'ILLION' (big number group). It follows 'undecillion' (10^36) in the sequence, so it's the *two-after-ten* -illion.
Conceptual Metaphor
QUANTITY IS SIZE / SPACE: A number so large it metaphorically represents an infinite or cosmic scale.
Watch out
Common Pitfalls
Translation Traps (for Russian speakers)
- Do not confuse with Russian 'дуодециллион', which traditionally follows the long-scale system (10^72). Direct translation can cause a 10^33-fold error in magnitude.
- Avoid using in practical translation; rephrase with powers of ten for clarity.
Common Mistakes
- Using it in everyday contexts. Mispronouncing as 'duo-decillion' (with a hard 'c'). Confusing its value between scales. Assuming it has a common plural form (it's usually treated as a quantifier: 'a duodecillion particles').
Practice
Quiz
In which context is 'duodecillion' most appropriately used?
FAQ
Frequently Asked Questions
It depends on the numbering scale. In the modern short scale (used in the US and most modern English contexts), it is 10^39. In the traditional long scale, it is 10^72.
Almost certainly not. It is a theoretical or scientific construct used to discuss quantities on a cosmic or combinatorial scale, far beyond any practical measurement.
In the short-scale system, tredecillion (10^42). In the long-scale system, tredecillion (10^78).
No. While educated speakers may recognise it as an extremely large number, very few know its precise value. Using '10 to the 39th power' is always clearer.