Definition

1. Noun:

   • A specific large number: In the United States and most modern English contexts, "trillion" is the number 1,000,000,000,000 (one followed by 12 zeros). In older British English (now largely obsolete), it historically meant 1,000,000,000,000,000,000 (one followed by 18 zeros).
   • A very large, indefinite number (hyperbole): Used informally to emphasize an extremely large, often uncountable, quantity.

2. Adjective:

   • Denoting a quantity of one trillion: Used to describe a noun as being equal to this specific large number.

Usage Examples

• Noun:

  • The national debt is measured in trillions of dollars. (The debt amount is in the range of thousands of billions.)
  • He said there were a trillion stars in the sky, but he was just using hyperbole. (He used "trillion" to mean a vast, uncountable number.)

• Adjective:

  • The company is valued at several trillion yen. (The company's value is several thousand billion yen.)
  • A trillion dollars is an almost unimaginable sum of money. (One thousand billion dollars is a huge amount.)

Advanced Usage

• "Tons and trillions": An informal, exaggerated phrase for a very large amount.

  • I have tons and trillions of things to do before the deadline. (I have an overwhelming number of tasks.)

• In scientific notation: 1 trillion (short scale) is written as 10¹².

  • The energy output was on the order of 10¹² joules. (The output was about one trillion joules.)

Variants and Related Words

• Trillionth (adj, n): The ordinal number (1,000,000,000,000th) or one part in a trillion.

  • She was the trillionth visitor to the website. (She was visitor number 1,000,000,000,000.)

• Note on Scales: Due to historical differences, the terms "billion," "trillion," and "quadrillion" can be ambiguous. The modern standard is the short scale (used in the US and most English-speaking countries), where each new term is 1,000 times the previous (a billion is a thousand millions, a trillion is a thousand billions). The older long scale (used in some European languages and historically in British English) defined a trillion as a million billions (10¹⁸).

Synonyms

• Gazillion / Zillion (n, informal, hyperbolic): An unspecified, extremely large number.
• Myriad (n, formal): A countless or extremely great number (often of diverse things).

Related Phrases

• "Thanks a trillion": An informal, emphatic way to say "thank you very much."

  • You helped me so much—thanks a trillion! (Thank you an enormous amount.)

• "Not in a trillion years": An emphatic way to say "never" or "absolutely not."

  • Would I agree to that deal? Not in a trillion years! (I would never agree to it.)

Adjective

1. one million million in the United States
2. one quintillion in Great Britain

Noun

1. the number that is represented as a one followed by 12 zeros
   • in England they call a trillion a billion
2. the number that is represented as a one followed by 18 zeros
   • in England they call a quintillion a trillion
3. a very large indefinite number (usually hyperbole)
   • there were millions of flies