Definition

1. Adjective:

   • Being ten more than seventy; equal to eight times ten. This is the cardinal number 80, used to describe a quantity or position in a sequence.

2. Noun:

   • The cardinal number that is the product of ten and eight. This is the number itself, represented by the numeral 80.

Usage Examples

• Adjective:
  • She bought eighty apples for the event. (She bought a quantity of apples totaling 80.)
  • He finished in eightieth place. (This uses the ordinal form derived from 80 to indicate position.)
• Noun:
  • Eighty is a multiple of ten. (Here, 'eighty' is the subject, referring to the number itself.)
  • The number on the jersey was eighty. (The jersey displayed the numeral 80.)

Advanced Usage

• "In one's eighties": Referring to an age between 80 and 89 years old.
  • My grandfather is in his eighties and still very active.
• "The eighties" (often capitalized as 'the Eighties'): Referring to the decade from 1980 to 1989.
  • The music of the eighties is making a comeback.

Variants and Related Words

• Eightieth (adj., n.): The ordinal form of 80. As an adjective, it means "constituting number eighty in a sequence." As a noun, it means "one of eighty equal parts."
  • This is the eightieth anniversary. (Adjective)
  • She received an eightieth of the total. (Noun)
• LXXX: The Roman numeral for 80.

Synonyms

• Fourscore (archaic): An old-fashioned term meaning eighty.
  • "Fourscore and seven years ago..." (From Abraham Lincoln's Gettysburg Address).

Related Phrases

• Eighty-six (v., slang): To discard, eject, or refuse service to someone. To cancel or get rid of something.
  • The bartender decided to eighty-six the troublesome patron.
  • We had to eighty-six the special; we ran out of ingredients.
• Eighty-twenty rule (Pareto Principle): A principle stating that roughly 80% of effects come from 20% of causes.
  • In business, the eighty-twenty rule often applies to sales from key clients.

Adjective

1. being ten more than seventy

Noun

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