9 definition

nīnĭ-lĕvən
September 11, 2001, the day on which four airliners were hijacked by terrorists for use in an attack on the U.S.: two were flown into the towers of the World Trade Center in Manhattan, one into the Pentagon, and the fourth crashed into a Pa. field.
proper name
7
5
September 11, 2001, the date on which two hijacked airliners were flown into the World Trade Center in New York City and another into the Pentagon. A fourth hijacked airliner crashed in open land in Pennsylvania.
noun
4
4
The cardinal number nine.
symbol
0
0
The date of the attack on the Twin Towers and the Pentagon in the USA, September 11th, 2001.
pronoun
0
0
The attack itself.
pronoun
0
0
Advertisement
An event comparable to 9/11.
noun
0
0

Other Word Forms

Noun

Singular:
9
Plural:
9-11s

Origin of 9

  • From the date September 11 written in numbers according the format used in the United States, which puts the month before the day.

    From Wiktionary