Definition

1. Cardinal Number:

   • The natural number following sixty-nine and preceding seventy-one; equivalent to ten multiplied by seven (70).

2. Noun:

   • The symbol, word, or group representing this number (e.g., "seventy," "70," "LXX").
   • (plural, the seventies) The decade from 70 to 79 in a century, especially the 20th century (1970-1979).
   • (plural, the seventies) The period of life between the ages of 70 and 79.

3. Adjective:

   • Amounting to seventy in number. Example: "seventy years"

Examples of Usage

• As a Cardinal Number:

  • There are seventy students in the auditorium.
  • Seventy minus ten equals sixty.

• As a Noun (Symbol/Word):

  • "Seventy" is written with seven letters.
  • The Roman numeral for seventy is LXX.

• As a Noun (Decade/Age Range):

  • My parents were married in the seventies.
  • Her grandfather is in his seventies and still very active.

• As an Adjective:

  • The book has seventy pages.
  • She received seventy replies to her survey.

Advanced Usage

• "The roaring seventies": A phrase sometimes used to describe the 1870s or 1970s, highlighting their distinctive social or economic character.
• "Seventy times seven": A biblical phrase (Matthew 18:22) meaning a very large, essentially unlimited number, often used to imply boundless forgiveness.

Variants and Related Words

• Seventieth (adj., n.): Constituting number seventy in a sequence; the ordinal form (70th).
  • This is the seventieth anniversary of the event.
• Seventyfold (adj., adv.): Seventy times as much or as many.
  • The investment yielded a seventyfold return.

Synonyms

• Three score and ten: An archaic or literary term for seventy (a "score" is twenty).
• LXX: The Roman numeral representation.

Related Phrases

• Seventy-something (adj., n., informal): An unspecified number between seventy and seventy-nine; a person aged between 70 and 79.
  • A seventy-something retiree.
• The seventy-seven (n.): Can refer to a specific group of seventy-seven, such as the Group of 77 (G77) in the United Nations.

Adjective

1. being ten more than sixty

Noun

1. the cardinal number that is the product of ten and seven