Definition

1. Adjective:

   • Coming after the nine hundred and ninety-ninth in a series; being number one thousand in order. This ordinal form indicates position in a sequence.
   • Constituting one of a thousand equal parts of a whole. This describes a specific fractional relationship.

2. Noun:

   • One of a thousand equal parts of something. This is the fractional noun form, equivalent to 1/1000.
   • The person or thing occupying position number one thousand in a series. This refers to the item at that specific ordinal point.

Usage Examples

• Adjective:

  • She celebrated her thousandth day of learning English. (She celebrated the day that was number 1000 in her sequence of learning.)
  • A thousandth of a gram is a milligram. (One of the thousand equal parts that make up a gram is called a milligram.)

• Noun:

  • The device can measure time to the nearest thousandth of a second. (The device can measure intervals as small as 1/1000 of a second.)
  • He was the thousandth visitor to the museum this year. (He was the person whose visit was number 1000 in the count for the year.)

Advanced Usage

• "To the thousandth": Refers to precision in decimal places, specifically three digits after the decimal point.

  • The constant was calculated accurately to the thousandth. (The constant's value was calculated precisely to three decimal places.)

• "The thousandth time": An idiomatic expression emphasizing that something has happened very many times, often with a sense of repetition or frustration.

  • For the thousandth time, please close the door quietly. (This is said to emphasize the high number of previous requests.)

Variants and Related Words

• Thousand (n, adj): The cardinal number 1000.

  • The book has over a thousand pages.

• Thousandfold (adj, adv): Multiplied by or consisting of a thousand parts; by a factor of a thousand.

  • The investment saw a thousandfold return.

Synonyms

• Ordinal (for position): 1000th (numerical symbol).
• Fractional: One one-thousandth, 1/1000, 0.001.

Related Phrases

• One in a thousand: An expression describing something or someone exceptionally good or rare.

  • Her kindness makes her one in a thousand.

• Not in a thousand years: A hyperbolic idiom meaning "absolutely never."

  • I would not agree to that in a thousand years.

Adjective

1. the ordinal number of one thousand in counting order

Noun

1. one part in a thousand equal parts
2. position 1,000 in a countable series of things